Dog Hair

What is an effective way to cut the matted hair, in large measure a dog without cutting machines?

My dog is old, and her hair has exceeded their legs and actually impede their movement. I assumed that would happen before your hair get so bad, so I thought I had recovered from the trauma preparation for their age. But he still has spark, but is miserable because they can not move very well because of the amount of hair. I have cut him, but I can not pay a professional and I have not cut the hair of the dog. The scissors are completely ineffective in most conflict zones. Is there any way to loosen the hair tight, mate so I can cut?

detangling shampoo and a stiff brush