Why not start some swimming classes with your daughter? if you're going back to work part-time you can then keep up the lessons on your day/s off and it gives some continuity. It takes months/years for them to learn to swim and I found it was good to have something planned for one of my days off (always felt a bit brain dead after rushing around at work so nice to have a regular outing planned in advance).
Is there anything that needs doing that you just couldn't do when you go back to work? We had some building work done, about 10 days of builders so not too bad, but I couldn't have done it when I was back at work full time. I also did a load of gardening in my last week of leave when DD was doing mornings at nursery to get used to going. Oh, and lots and lots of cuddles with your DD .