Tree Trimming

Tree Trimming

I was wondering if anyone knows of an online resource for tree trimming that is actually reputable. I'm wary of a google search because you just never know the people's reputations. Specifically I am in zone 8 with two Arizona Ash trees in the front yard. The branches tend to bend easily and sag, making an unattractive border to the tree. I'm looking for advice on how to trim it myself. I have a small tree-trimmer available to me. thanks in advance for your help!
Baking with garden

Baking with garden

This is the view when you first walk in

This is the view when you first walk in

sign of spring

sign of spring

See what happens when I take photos!

See what happens when I take photos!

The Rasberries are coming

The Rasberries are coming

Try marigolds with your veggies.

Try marigolds with your veggies.