Yeah OP please use a razor? Razors are made for shaving, trimmers are for trimming.
Actual tips for shaving I can give you:
Stretch the skin a little with your free hand to make sure you have a smooth surface (helps you not cut into the skin) (unless you have perfectly smooth non wrinkled balls)
As with any body hair I'd recommend trimming before shaving so the hairs are shorter and easier to shave
In the same vein, frequent shaving helps keep the hairs short and makes shaving easier
As someone else said it might be nice to use conditioner instead of shaving cream. Personally I never use shaving cream anyway because it doesn't help me at all lol. It anything make sure your skin is hydrated, it'll make shaving a lot smoother