In my experience the best way to land a grab is to either punish an opponent's spacing error or you can also bait your opponent to try to punish something you space well and counter with a grab. It's risky but you can also Nair at them or cross up Nair then grab when they attempting to punish you. In addition you canthbe a 3/4 charge splat bomb to bait shield and see how they counter it and save that information for later or push your advantage if you guess right, fox trot and dash dance are also both vary solid options in neutral, down tilt is also good for stuffing over extensions quickly
From grab you can buffer a pummel and get a second then buffer your throw and start a combo from a throw. Once you get a throw you can pressure your opponent after your combo and push your advantage further.
Your win conditions are to do one of 3 things:
Edge guard your opponent
Land a roller and follow up on it
Get a grab and the up throw up air confirm
Obviously you can get a hard read to kill them if need be.
That's all for this part in the next part I will go over advantage/disadvantage state.
Until next time Stay Fresh!!