Cutting pubic hair with comb and scissor doesn’t get any more basic and cost-saving than this. Simply comb all your hair smooth and lay comb flat against skin, then cut hair above comb. The comb acts as a protection so you don’t nick or cut your delicate skin. If you use a fine-tooth comb you'll get more smooth and even results versus just using a regular comb.
If you don't want the hair very short, you don't have to lay the comb right against skin. But just be careful to follow the guide of the first cut you made so the hair is even, instead of looking choppy.
Read more options for grooming down below for men and women: How To Trim Pubic Hair