The Essentials

These are tools that will be used across the entire game.
Hold shift to walk. Prevents you from falling off of ledges. Makes you less likely to knock things over or spill things.
Left click to mop.
Right click to smack things to dislodge them if they are stuck.
Hold left click and move your mouse to rotate an object.
Tap left click to reset an object to default orientation.
Tap right click to release the object.
Tap E to throw the object.
If you move your mouse rapidly and throw or release an object, you can throw objects extremely long distances.
Left click to detect viscera and blood.
Right click to detect trash and bullet holes and bullet hole-like decals.
The Sniffer detects mess around your current position, not where you are looking.
Gamers don't look up! If the Sniffer is going crazy and you can't see anything, look up!
If you don't know if something counts as trash, always use the Sniffer first. Incinerating non-mess objects is a waste of time, and you risk incinerating secondary objectives.
The Laser Welder is for fixing bullet holes, laser holes, lightning scars, and acid burns.
Do not fire it for too long, as it will overheat itself/the surface and create fire which will produce ash.
The time to fix bullet or laser holes increases with the size of the decal.
It approximately takes this long to fix these common decals:
Normal size bullet hole: 1.15s
Normal size laser hole: 1.4s

To more easily dispose of large objects that are far from the incinerator, you can use the Laser Welder to melt them into smaller pieces so you can fit more in a bin. If it makes a large meatball which would be inefficient to put in a bin, you can just throw them towards the incinerator, as lasered objects don't leave blood splats because they are cauterized.
Lasering objects that have already been lasered (melted synthetic objects and meatballs) causes them to vanish, but it takes a very long time, so it's more efficient to just throw them all toward the incinerator if they are too large for a bin.
If the J-HARM becomes stuck in the up position with the lower controls unreachable, smack a heavy object into it, such as a crate or barrel, until you can reach the controls or it tips over and collapses itself.
You can hold left click without rotating to activate items like flares and mining explosives. You can also strike flares hard against a surface to light them or hold them in fire or in the way of a laser.

This equipment only appears and/or is only useful in specific maps.
Can absorb a little mess extremely slowly and push things very slowly. A worse mop.
Useless except for Core Sample where it is needed to sweep up crystal dust.
Used to bury Pit Monsters (the mouths in the floor) in Unearthly Excavation and Penumbra.
Teleporters comes in pairs and transport one item at a time, OR multiple items if they are inside of a Quantum Bin.
Can malfunction by duplicating items or killing Janitors instead of teleporting them.
Used to help clean graffiti in Uprinsing only.
In addition to cleaning the mop as usual, they are used to stop TNT from exploding if it is lit, and used to safely dispose of TNT in the fire - this mechanic is only needed in Santa's Rampage as you can just leave mining explosives alone in other levels.

You might think "I should get rid of all the trash and body parts before mopping up, because this is logical in real life!", but you are wrong. The opposite is actually true in this game.

Because;
- walking over body parts doesn't leave footprints,
- viscera doesn't leave more blood if you mop underneath it unless you cause the object to move by mopping too close,
- and leaving fresh footprints is extremely inefficient,
the most efficient order to clean a level is:

- Laser things that will cause more mess by being lasered, such as reducing the size of bodies, getting rid of roots etc.
- Mop everything.
- Use bins to remove body parts and trash, while throwing large lasered objects toward the incinerator.
- Fix bullet holes and other similar decals.
- Do secondary objectives.

Remember to stack 2 buckets when transporting water.
Incinerator efficiency increases the more doors that are closed.

You can only open a locked door if you are able to type digits into the screen.

Passwords for keypads can be found in notes, data logs and even written in blood around the level.

If you misplace a code in any way, you can still get the door open by hacking the keypad.

The codes for the doors around the office are randomly generated every time the office is loaded and aren't written anywhere, so you need to hack them, there is no other legitimate way.

To hack keypads, spam a single number at a time for the entire code length. If a correct number is in the correct position, there will be a "click" noise and the screen on the keypad will flash green for a split second.
For example, if you press 1 for an entire code's length, and the screen flashes the second time you press it, then you know the second digit in the code is 1 and that it is not repeated.

To get a higher score, you can:
- Do secondary objectives, like stacking items in designated areas and refilling medical supplies.
- Collect PIDs (the usb sticks) and upload them to the punchomatic by holding them against it.
- Fill out paperwork on the punchomatic for the whole incident and for each death.

If you do at least some of these things, you can get well over a 100% score even if you haven't cleaned 100% of the mess.
All of these extras are found below.

Stack various items inside the designated areas to earn extra score.
Stack areas are color-coded and labelled with what they need to be stacked with. You just need to look carefully at the floor.
To count as being inside the stacking area, the center of the item must be inside the border.
Crates and barrels need to be upright to get points for stacking them. Any barrels not upright, no matter where they are placed, will deduct points.

"Crates" (Orange text): All normal crates (including the spherical crates), and cardboard boxes.
"Crates" (Green text): Medical crates (the white crates with a green cross).
"Med-Waste" (Green text): Medical waste crates (Only in Caduceus).
"Barrels" (Yellow text): All barrels (or only yellow barrels, if you are in Unearthly Excavation).
"Barrels" (Blue text): Blue barrels (only in Unearthly Excavation).
"Nitrogen" (Blue text): Cryogenic storage canisters (only in Cryogenesis and Evil Science).
"Signs" (Yellow text): Wet floor signs (only in Evil Science).

On most levels. Use the vending machine to vend them.
Carry them to a first-aid wall container, reset the orientation, and release it when it is in the container and it should snap in. You can then close the container.
Only in Hydroponic Hell. Use the vending machine to vend them.
Remove the weeds from the planters and replace them with seeds until the display says that it is full.
Only in Revolutionary Robotics. Use the vending machine to vend them.
Get rid of the broken guns on the ceiling and replace them with new ones, then attach ammo that can also be dispensed from the vending machine.
Only in Incubation Emergency. Use the vending machine to vend them.
Replace all light bulbs and eggs in the various cases throughout the level.
Only in Unearthly Excavation and Penumbra.
Use a shovel to fill them in with dirt or sand.
Only in Unearthly Excavation.
Must be incinerated.

To file paperwork, choose the first option on the Punchomatic and scroll to view the entirety of pages.
Use environmental clues along with notes and data logs found throughout the level to determine the incident particulars and the cause of each employee's death. Definitions for these are linked at the end of this section.
To get some easy bonus points from paperwork quickly without paying much attention, try to find something in common with all of the dead. This is often "Slain", which means they were killed by a non-human entity such as aliens, mutants or robots, and just give them all those checkmark(s).

For some reason, all mutants count as aliens even if they seem man-made with no alien influence, but not all aliens count as mutants. For example, Hydroponic Hell has mutants AND aliens, even though aliens are never mentioned. Whereas Pestilent Penitentiary only has aliens and not mutations.
So if you see evidence of mutations or mutants, then "aliens" MUST also be checked.
The bonus points you get for open text fields in paperwork only depends on the length, so you can just mash your keyboard or copy and paste spam to fill up the boxes. Even the union number is like all other text fields, it doesn't matter what you put in, only the length.
The only box you should leave blank is the one UNDER where you put your union number, as this is you complaining about the company to the union, so the company will punish you.
Full list of definitions for Incident Particulars: https://steamcommunity.com/app/246900/discussions/0/357287304439828118/
Full list of definitions for Causes of Death: https://viscera-cleanup-detail.fandom.com/wiki/Punchomatic#Cause_of_Death:_Definitions

If any mess is unreachable or unable to be unstuck, you can type KillNearestMess in the console.

You can access the console by pressing ~ or @ depending on your keyboard.

The devs fully expect you to use this feature because things get stuck and broken so often, that using commands like this doesn't disable achievements.