The trick to avacados is the ripeness
I always try and buy Haas avacados. A ripe avacado will be a darker purplish green. It will have some give when you presh in on the skin, but will not be mushy. Avacados ripe at room temp. If you want to slow the ripening process put oin a refrigerator.
To cut one, wash the skin place on a paper towel and cut the whole circumfrence with a sharp knife down to the pit. Cut all the way around. grap the two pieces in either hand and twist. The avacado comes apart, one with the seed the other without it. Take the seed out with a spoon or pop your chefs knife it it and lift out. If it is properly ripe the skin pulls away, or you can run a large spoon next to the flesh and the skin, or you can skin with a paring knife. Slice and cube according to what you want then
Spray with olive oil and grill
quickly with grilled golden pineapple rings if you want to try it a different way than most