Regarding picking styles, there are primarily 3 different types of picking. The most popular and widely used form is alternate picking, which is, of course, as it sounds: every note is picked up/downup/down. But another way to pick that increases facility and speed is economy picking. When using economy picking, things are simplified - when switching strings the stroke need not be the opposite of the last stroke, but it can be the same. This is hard for me to explain. Use the search function in the toolbar and search for picking or economy vs. alternate, etc...

I've always been a proud user of economy picking because it makes more sense to me. However, the decision on what picking style to use comes down to you. I cannot tell you that this style is better than anything else, but it does work for me. Experiment, and see what you like the best. I know plenty of shredders who use econ., and plenty that use alternate.

Most of what you learn about this stuff comes from experience. Play around with all this stuff as much as you can, and the answers will become clear to you.