Every day, I go to my Watchlist and add the latest profiles to a spreadsheet I made in Google Docs. I have a column there where I note additional sources I want to add. I bookmark whatever tabs I have open using a chrome app that lets you bookmark all your open tabs at once, and every couple of days, I copy all those bookmarks into Google Docs and go through them, organizing them by topic.
The most useful thing about the Google Docs spreadsheet is that I alternate among families and projects. So today I added a husband to a previous profile, and worked a bit on their children. Since I didn't really finish working on them, I kept them at the top of that page and made a note about what I wanted to do with them next. Later today, I can go in and work on that same family, or I can go to the next tab (the next surname or project) and work on the top person there. Here is a link to my spreadsheet if you want to see what in heck I'm talking about: https://docs.google.com/spreadsheets/d/1FFf_SuR5hAE3J1IXAJBU5yZihoJ-ZnLRKjTnECVSJTA/edit?usp=sharing
Sometimes I add specific sources (e.g., need to add 1910, 1920, 1930 censuses). Sometimes I just make a note about where I left off.
I've only been handling my watchlist this way for a couple of weeks, but it has greatly helped me to make sure I'm working on every surname and project regularly, and to keep track of where I left off.