I'm making a new follower for whom you need to do a fetch quest before she becomes a follower. I'm using a custom voice for her.

I've gotten everything up until the end of the quest and you wish for her to become a follower. How do I set a condition upon being a follower? How would I do her factions in order to make this happen? Also, how would I do that with a custom voice?

Please help me. I love learning how to make mods, but I just cannot figure this one out.

Scripting a full blown follower that you command with more complex instructions is fairly complicated for me as I'm not very good with scripting. However, if you just want basic stuff, I gave one of my NPC's a follow package that only runs if my quest is at a certain stage. He will follow me anywhere as long as that stage is valid, and he works great. I can't really command him in terms of follow distance, aggression and so on yet, but I think you might be able to set his dialog so that different topics set different stages and have packages with conditions to only be valid during those stages. For example:

Stage 20 - Go back home and wait for me or whatever. (travel package with specific location set to go to)
Stage 30 - Follow me, but keep your distance (Follow package with wide radius set)
Stage 40 - Follow me closer (Follow package with small radius set)
Stage 50 - Hang out here (sandbox that location)

I haven't tried any of these yet, but when I get to the point that I start tweaking my follower a little more this is what I was going to try. Someone else with more experience might help more, but I believe this method should give me a few basic functional commands.