Easy High Score
When playing a big star that's says try me pops up. Click it and if it is a golf ball you can start the trick. When you have the golf ball throw it in his mug, if you miss it doesn't make you start over. You can use this cheat forever. If you hit him or the door then the cheat ends.
Extra point or two
If you throw the eraser, cupcake or paper into his cup, you will get an extra point or two. Do not use the pencil it won't work.
Office zombie thirsty no more
To get this achievement throw the couldron at him so he (the zombie nerd) turns around, then throw the couldron again and he will drink it; this may take a couple tries so be patient and keep trying.
Using the in-game fan
If you simply tap the fan, it will load onto the desk and you can throw it as many times as you want. Wind will still apply, so be carefull.