In the Black Widows Lair
Go along the bottom level until you get to the end. Climb up behind the guard and get above him on the boxes. When you see the female guard (third level) walk over and turn away, jump up and sneak behind her until you get near the chair. Jumping on the springy chair should send you up and left to the locked door. (You have the key card.)
In the Museum (daytime)
Take the Underground Tour, and when you return, you can apply for a job.
In the Museum (night)
Slip past the Security Room while the guard isn't looking, and hide behind the statues to avoid the lasers as you go to the right.
You have to get a balloon.
In the clown store
First you get out the chair by moving your mouse and then you get passed the guards i think if not let me check again.......
Stay on the bottom level until you get to the left side, and the jump up on the boxes behind a guard. Then, if you time it right, you can jump to the third level, sneak past the guard, and onto a very bouncy couch. Then you use the Black Widow Card Key, to get into the locked door!
You must go on the Underground Tour before you can apply for the job at the museum.
You have to get a balloon.
drink bleach, everyone knows that...
When you get past the Black Widow's guards, then you will use it to enter her layer. Have fun! :-)
Go carefully. When the guards are about to see you, hide behind the things there. When you get to the top, use the key card you should've gotten earlier.
try and stay out of sight of gaurds
In the clown store
all you do is get a balloon and sneak past them but pace yourself.
The key card will open the door in the Black Widow's lair, once you get past the guards. (see related question)
you avoid all of the guards
There are no snowballs on Counterfeit Island. (see the related question)
It is the last part of the island, when you have discovered the stolen painting and get kidnapped by the Black Widow. Get past her guards and use the key card to begin the final battle.
When she leaves you in the chairs, she goes to her treasure trove of stolen art, where you will find her right away, as soon as you get past her guards.