How can I quick edit member and client notes without going into their profiles?

Member - 

A quick way you can enter notes for the member without going to the members profile, is to go to the toolbar on top and select member.

Select your member, and enter your notes and hit save.

Client - 

You are also able to do this quick edit with client details under the client tab next to the member.

Select your client, and enter your notes and hit save.