Here's what I do:
wear pants with easily accessible pockets (cargo pants etc), no belt, and easy to get on and off shoes. Put EVERYTHING in your carry on/laptop bag prior to getting to security except for a photo ID (drivers license) and your boarding pass. Keep all your liquids/gels in the plastic bag, and in an external pocket that's easy to access on your carry on.
Keep the laptop as easily accessible as possible as well. When you get to the checkpoint, put all the small items, as well as your shoes into one tub, your laptop in a separate tub by itself (sometimes they don't make you do this, sometimes they do). All you need once you get to the checkpoint is your boarding pass, so you can put your ID back into your pocket, or into the tub with the small items.
Put your shoes through first so you can put them back on while the rest of your stuff is getting scanned. That's about it.
I don't know about Tennis rackets. I haven't seen anyone carrying one around in a while, but I don't think it would be a huge deal either way. Worse comes to worse, ask the people at the airline counter at check-in. What you DON'T want to do is have to shuffle back and forth to ticketing with stuff.
Good luck! And there will always be someone there who is worse than you at the whole thing too.