I take the art of applying a screen protector very seriously.  Over the years, I've refined my process to science that yields fantastic results.  To help with this, there are several tools you can buy to make sure everything goes smoothly:

1) Metro Vacuum DataVac: this is leaps and bounds beyond using compressed air.  An electric duster gives you more power and an even stream of air.  It also will never run out like compressed air, and won't leave any residue.  Just be careful you don't blow anything away during use.

2) Desiccant Silica Gel: after applying a protector, there may be some moisture trapped between the screen and the protector.  Using a desiccant tool like this will absorb any residual moisture and help form an amazingly tight seal.  An added bonus is that when the gel stops working effectively, you can just stick it in the oven to recharge it.

3) Screen Cleaning Kit: it is important to have good screen cleaning solution and an excellent cloth that won't leave any residue.  I'd recommend a set like this.  It helps to have several cloths, so the whole operation can rest on one, and then you have another to use to clean and wipe the screen.

Hopefully you'll find this equipment helpful.  To read my comprehensive step-by-step guide on how to apply a screen protector perfectly, click here.