Union apprenticeship sign-ups near Denver - any advice?

I heard of an apprenticeship with paid on-the-job training for people changing careers. There are 14 people counting on me, so I am trying to be careful. Applications close in 9 weeks. What do you wish you had known?

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.

Bring your transcripts and any proof of work history. They asked for both in the interview.