Electricians on FABO - I want to add a 60Amp sub panel

Hello folks. I am looking to add more juice to my detached garage.
Currently, I have just a 20Amp line buried and going out to the garage (there when I moved in). 10 years ago when I bought the house, the first thing I had done was to have a 200 Amp service entry cable and 42 breaker box installed by an electrician. I have done some work with electricity since that time, installing dedicated 20amp outlets, running a new 220v line for a stove, etc. I am comfortable doing a project like adding the sub panel but I need guidance. I understand I would need to connect a 60Amp breaker in the box in the house, bury the line I connect 18inches, and install a 125amp panel in the garage with a 60Amp breaker at the top. I would use #6 wire and placed in conduit. Do you have any tips? suggestions? Do's and Don'ts? I would appreciate any help you could offer. Thanks!