I am doing a fresh install of zencart, going from 1.3.8 to 1.3.9

I can't really remember how i installed 1.3.8 as alot of it was guess-work and following tutorials.

I am scared about installing 1.3.9 and have no idea where to start. Are there any details such as SQL i will need in order to install it and get it working, and where would i find them? thanks!