Here are some tips and tricks I’ve picked up over the years while working with Rewrites that make creating them a little easier!
The ‘Notes’ Columns

Swap ‘Info’ column for ‘Notes’
The more Rewrites you use the more sense it makes to swap the ‘Info’ column for the ‘Notes’ one
Right-click the the bar with the column names (highlighted in the screenshot) -> untick ‘Info’ -> tick ‘Notes’

View modified Requests at a glance
Now you can easily see all Requests that have been changed by your Rewrites
The Repeat button

Use the ‘Repeat’ button to test your Rewrite Rules work
The Repeat button is fairly self-explanatory; it will reload/re-send a network Request
This button becomes incredibly useful while creating your own Rewrite Rules. Each time you modify and retest your rule, you can click this button to fire off a new Request to quickly check if your rule works. No need to switch back to your browser/app to trigger a new Request!
Constructing your Regex

Use a separate Regex tool to create your expressions
I suggest using an entirely different Regex tool/website (regex101.com and regexr.com are great tools) to construct your Regex expression
You want to be 100% sure your Regex works BEFORE you copy over to your Rewrite. Debugging Rewrite Rules can be tricky!