Before the first jump of the day, perform the same basic equipment check that you were taught during your training program. Develop a routine and stick with it, but make sure that it includes, at least, the following.

Take the webbing that holds the rings in place between your thumb and finger and manipulate it gently. If left unattended for a long time, it can take a "set" and make it harder for the ring to swing down and pass through the ring beneath it.

Check that the cutaway housing grommet meets the riser grommet, and that the cutaway cable is not trapped between them, also that the cable end is seated in it's protective pocket.

Check that your reserve pin is seated, that the closing loop is intact (and not frayed), and that the rigger's seal is intact.

Check that your main bridle is routed correctly, that the pin is inserted properly and in good condition, and that the main closing loop is intact and not frayed.

Check all of your handles to make sure they are seated properly, that your riser covers are in place and will stay seated and that your pilot chute is housed properly.

Also check your hardware, friction buckles and snaps to make sure that they are in good condition.

If you use an AAD, check it and calibrate it before the first jump of the day, also check any other battery powered back-up devices such as audible altimeters, digital altimeters etc. for battery strength.

Then, before you jump, check all of your equipment such as goggles - make sure they are not cracked or badly scratched, check the strap (or bungee) for wear, inspect the glass on your altimeter and the strap. It is way better to find problems with this stuff on the ground than in the air.