You can do either.
It's cheaper do it yourself, however, the initial cost of the grooming equipment is high.
I'd originally taken Charlie to a groomers, but I couldn't find one that did exactly what I wanted them to do (proper show cut)...so I've been helped by someone on here and she's shown me how to do him myself, I still take him to her to do as she does it quicker and better than I do, but I'm learning so I'm happy.