To block your own visits on your website on Safari you can use the about:blank extension. You can download about:blank via the Mac App Store.
This is external software, so we can’t guarantee your browsing data is safe. Use at your own risk.
To install this extension and use it for Simple Analytics you can follow the steps in this tutorial.
You will need the script URL at some point:
https://queue.simpleanalyticscdn.com to the block list.
On iPhone you can download about:blank on the App Store. It should sync your block list when you have iCloud enabled. If not you should add the above URL(s) manually.