Big question! It depends a lot on your own level of expertise, patience, confidence, willingness to learn and tolerance of your mistakes
Personally I don't have the confidence to trim Morgan myself although I tidy up his feet between proper grooming visits and I try to hand -strip his head.
A lot depends on what sort of look you're after. There are sometimes sad tales on here from cocker owners who were not at all happy with what grooming parlours had done to their dogs. Not enough groomers seem to be particularly skilled at cocker trimming and dogs can end up being shorn all over because it's easier for the groomer that way. Of course you can also strike lucky and find a groomer who will do a super job for you.
Are there other cocker owners near you? if so, do you like the way their dogs are done? Ask where they go.
I didn't want Morgan clipped and I've been very lucky and take Morgan to a CoL member who shows her dogs so she knows exactly what's best for Morgan (I don't show him but I like a reasonably showy look for him) She's brilliant with him, he always looks good and it means I haven't had to learn how to do it myself!
Your Bruno is a bit young for proper trimming just yet as he'll still have his puppy coat, you don't want to be in a rush to do much to him at the moment. At that age I was just starting to be able to do a bit of stripping on Morgan's head but his feet were like floor mops and I took him to a grooming parlour just to get his feet and nails done.