Milk first (barring tea of course!)
Get your phone away. On both my trial days I ignored it to the point of "you know you can answer your phone you know"
Be alert. Even if it's just a little job of all you're doing is passing screws. Think of what they need next and be ready with it.
Put the effort in because being an apprentice might be carp now but grin and bare it and think of those quals.
Buy your own tools. Even if it's just a hammer, level, driver and snips.
Our recent apprentice refused to buy tools other than a terminal driver all year with "I can't afford it" whilst going out every weekend. He didn't last long unfortunately.