Exercising schedule 2013

So, aware that if I try and start with 3 exercise sessions a week it will only last a short time... I've got a plan;

• January - Exercise once per week (x1)
• February - Exercise twice per week (x2)
• March - Exercise three times per week (x3)
• April - Exercise three to four times per week (x4)

I feel that exercising once per week in January is achievable. I am trying to work out what exercise I am going to do on Saturday. At the moment I am trying to arrange going running with friends, failing that I will go for a swim, or go to the gym again. I'd rather do something other than the gym as I went last Saturday. If I go swimming I still need to work out an exercise plan for doing swimming for an hour as I haven't been able to swim a whole hour before.