Clean your bearings. If you get water or sand in your bearings, you should remove them, clean with solvent (EG, WD40), and relubricate
Lube your bearings. Light oil is fastest, but repeat weekly. Try CRC brake caliper grease- a synthetic with rust preventatives, it's faster than other greases
Replace your brake pad. There is a wear line on the pad -- replace the pad before you get to this line
Rotate wheels on left and right. Your wheel rotation should include swapping left and right skates, so the wheels on your dominant foot do not get smaller
Rotate your wheels. This evens out the wear on inside/outside of each wheel, and among the wheels. Consult your owner's manual for recommended frequency