I wouldn't go any smaller than the .03 tip, or you'll surely have trouble spraying the pearl paint without thinning it, which means a lot more coats. If you go the thinner route, use the reducer/thinner that Createx recommends, or a small amount of Windex. Too much thinning can make the paint film weak, and make it bond poorly.
Do a test on a piece of PVC pipe with a small batch of thinned paint first to make sure it works before you start painting a lure.
Heat set after each coat with a hair dryer. Start on low speed fan and high heat, so you don't chase the wet paint around on the lure, and then finish with the higher fan speed, if you have a two speed/heat setting hair dryer.
The hotter you can get the paint the better it sets.
As Downriver pointed out, this is really T shirt paint, which is meant to be heat set with an iron before it's washed, so it likes heat.