I have been doing my own grooming as well and honestly it's been really pleasant. I would recommend getting a pair of good thinning scissors to do top grooming (bottom grooming I usually use a barber's razor) as the thinning scissors are far more forgiving when it comes to fuckups, it's been growing steady but I always put it in its place with the scissors. A few cuts here and there are key when it comes to taming it and reaching your objective

If you use a machine straight away you're definitely gonna end up looking crazy the first NUMEROUS times

stop using shampoo forever

I would like to hear Athin's advice