Having just gone through anal-gland-removal with my Maggie, thought I'd jump in with our own experiences.
My Miss Mags is three years old, and since her puppy days has had trouble with her glands. At first, she was expressed about every two months; in between, she gave me clues when they were bothering her, ie: lots of licking, snapping at her bottom, sitting down gingerly, etc. The vet showed me how to empty them, but I never felt confident doing it; the vet seemed to remove more substance than I ever did.
As time went on, her episodes became more and more frequent; I was told this is a normal pattern; we were emptying every ten days, and if I didn't do it that often, then she was soon sick with them; even had a couple of seizures from the pain (she is prone to seizures anyway.) She was on antibiotics once/month from October to January.....and finally had them removed two months ago.
I was reluctant to have the surgery done when she was young, since the anal area is heavily innervated; This means that recovery is painful, and if a nerve is cut, the dog can become incontinent for the rest of their lives. Wasn't willing to risk it.....until she became sick CONTINUALLY with them.
GOOD NEWS HOWEVER!! My vet was recently trained in a new procedure to remove anal glands which involves LESS cutting into the buttocks, thus faster recovery time, and less chance of complications!! It involves a special catheter inserted into the anal gland, which is then filled with air, making the anal glands easier to locate EXACTLY, and with a surgical assistant, can be gently pulled closer to the surface as the vet excises the area.
Maggie did GREAT with her surgery, and is pooping like a trooper now. BEST of all, no more illness and constant pain for her, and no more heartache for me. I wish you luck with the anal glands, but if you don't feel confident expressing them yourself, then make sure it's done regularly by a vet or a groomer. It will lessen your overall medical bills, as an infected gland is a nasty thing to deal with.
P.S. My vet allowed aspirin for pain relief following her gland expression sessions; occasionally she even needed prescription pain meds if they were really bad.