Good luck on your first build!
Do you have a multi meter? I didn’t have one when I started but quickly found out it is pretty useful/necessary. As a habit, I use it to check the footswitch, whether I use a mini board or not, and all the other wiring connections before I plug it in. I also use it to check all the resistors, in addition to using the color codes. Oh, which is another tip, I double and/or triple check the parts before I insert them PCB.
And when there is a problem, many times the guys here will want to know certain measurements to help diagnose what is wrong. I’ve been there several times