Rinse out your wetsuit, harness, and maybe bar and lines in fresh water and hang em up to dry in the shade.
If your kite is dry, just fold it up and put it in it's bag. Don't leave it anywhere hot, like the boot of your car in the sun.
If you have pulleys, check them often. Sand can clog them, a seized pulley can rapidly eat through a bridle line. Some guys use a silicone lube on their pulleys.
Check your lines as you set up your kite.
Check your safety releases as often as you like.

That's about all I can think of, a lot less complicated than my mountain bikes.

And if you have zippers your kite bag then use some vasso and loob them up in the off season so you can open your kite bag the next summer!

One other thing if your kite gets rinsed in the shore break or is regularly ending up full of sand.
Ocassionally when deflating run your hand up between the leading edge and the canopy and remove any sand caught there.. Can wear the kite faster. PLus check if your tips wear from self launching on beach.. any holes patch them straight away ..

Would you guys recommend a vacuum in between the leading edge & canopy when it's in the garage?

Ahhh huh - thanks big man. You were the bloke who sold it to me

that can be a difficult one...........

Check where your front lines cross ie: after a back roll your front lines will cross check this area for wear. also where the pigtails attach. You will find that the first sign of wear will be a slight freying of the outer sleeve dyneema.

Most lines seem to have an inner core usually white with an outer sleeve ( red, grey yellow etc..... often the outer part can look very worn but the inner ( strength section ) will be uncompromised.

Many lines that look like they are finished will end up lasting another season, but it can be risky and it depends on how you load the lines ie : jumping and kiting generally will not put too much strain on them but looping or shock loading the lines can very quickly bring them to the end of their life.

Skock loading occurs most often after you swing under the kite and it backstalls ( drifts back ) before powering up again whilst the lines are slack. hope that makes sense.

If in any doubt replace them as you dont want to spend each session worrying about it ( buy a roll of the line stuff ......its much cheaper ).