I am astonished at how many people are not familiar with their own equipment. I am not talking about how to adjust whether your camera adjusts exposure in 1/2 or 1/3 stop increments, I am talking about changing simple settings.
Read. Test. Practice. Rinse, lather and repeat.
Know where the ‘important’ buttons are on your camera. Know how to use your ancillary equipment like strobes and triggers. If you have a lighting modifier – put your strobe in it and see what sort of spread and fall off you get at different settings. This is not rocket science, just something that you should do *before* you use it in a shoot.