This is completely up to you - there is no "right" answer!
In our opinion, we don't recommend sending more than 3 emails per week.
If you post more than 3x each week - that's not a problem! Thanks to our "Customize Email" option, you can use emails as a recap of recent posts so you can post as frequently as you want.
Just use the "Customize Email" option after you click "Notify", and customize the email so it is a recap of what other posts you have made and not notified people about. That way you can post as much as you want without spamming your fans with a ton of emails!