When you meet your opponent at the court, you should introduce yourself then immediately spin to see who wins the spin.

Reasons:
1. You need to warm up on the side you intend to play on to begin the match.

2. If you are playing doubles and you are going to be the 3rd or 4th server in the match, take a lot of overheads to warm up your serve motion, hit a few serves as everyone else is warming up then focus on returning their warm up serves (not for winners but back to them) since you will play 2-3 games in the set before you actually serve for the first time but you may return serve 1-2 times. Be ready to break serve by getting those returns in from the start.