Trades apprenticeship applications open in Raleigh - any advice?

The training centre near Raleigh opened applications for apprenticeships in electrical and welding trades. There are 18 people counting on me, so I am trying to be careful. The application needs a diploma or equivalent, a driver's licence and a short aptitude test. What do you wish you had known?

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