Screw motivation. Seriously...do you motivate yourself to brush your teeth? Do you motivate yourself to do other things that may not be fun but just have to be done? There is a point that Mark makes about doing what you feel like doing and missing the occasional workout is no big deal, but you arent there yet. For now, write the workout, walk, whatever in your scheduler in pen.
OK probably your schedule is electronic, I may be the last of the luddites. Whatever. Put it in the same way you would put in a doctor's appointment or a customer meeting and just do it. Make it a walk if swimming sounds like too much effort. Walk for 15 minutes. Once you get past 15 minutes 90% of the time you will probably want to keep going.
Can you walk any of your errands? My friend never does any conventional exercise, but she walks to the grocery store. Which means she has to go almost every day because she only gets what fits in her backpack to take home. It's perfect because it is downhill to the store, and uphill home carrying the full backpack. Some times she wears it and hikes up. Sometimes she takes out smaller items and walks home carrying them doing bicep curls or overhead presses.
MTA: Or if you really need that kick in the butt...tell yourself you have to either go out and move or scrub the toilet or someother chore you detest
MTA: because it is rare I dont have more to say
"When I got too tired to run anymore I just pretended I wasnt tired and kept running anyway" - my daughter Age 7