Cutting it will not make it grow any faster, hair grows at a pretty consistent rate.
Let it grow, if you see split ends, get it them trimmed off (or let it go).
Couple things that help.
Don't scrub the heck out of your scalp. This breaks and pulls out hair.
Only use shampoo on your scalp, enough runs off to clean your hair.
Find a shampoo that doesn't have sodium laureth sulfate, this strips the oil from it. It's too aggressive, especially for longer/older hair.
Don't shampoo more than twice a week. I usually shampoo twice, and condition as needed.
Find a conditioner that works for your hair type. Some is good for thin, some is good for thick. Some is just junk.
Olive oil makes for a great conditioner once in a while. Put it in and let it sit as long as you can. Then shampoo and condition.
Beware silicone additives. If an additive says "cone" it's a silicone to make your hair feel better than it is. Great if you want it to look healthy and shiny, just beware that this is a false sense of healthy hair.
Depending on how long you go, also can change things. Below the shoulder blade, expect to shed more hair as you tend to lean against it when sitting and laying. Expect to have to sit and lay down differently a bit. Also, it becomes an issue in other ways too. You always have to be aware of it is when you are working on things.
I love long hair (down to my waist when combed out), but I am considering cutting it just above my shoulder blades or to my shoulders. It's a lot of maintenance and I go through a lot of conditioner.
