Here is a good video I got off of YouTube where a gentleman is demonstrating how to tint the end of wires. He has a cool cable holder, looks like part of a guitar pickup spring load system that he modified.
You can use anything, I use vice grip pliers a lot because they are handy. Just be sure not to tighten them down too much or you will nick the metal of the jacks. There is all kinds of commercial wire holders if you look around. I’m sure there are roadies that can hold the wires in their teeth as they solder. LOL
One other thing is I would put a fan on my work space to suck out the fumes. You don’t really want the fumes up in your face. If you are going to do a lot of soldering there are different commercial ways to deal with fumes.
Also as an added tip, always buy the best tools and soldering equipment you can afford when starting out. Repair equipment is no different than music gear, you can start out with the cheap stuff but as your chops grow you always go back and buy what you wished you had bought in the first place. Am I wrong?