A few tips
1) Exercise first thing in the morning if you can when you're fresh and fantastic, then it's done for the day and if you get home absolutely exhausted, you can fall in a heap in bed knowing it's been done already
2) Know that you're just making up excuses and bloody get off your butt and do it. Right now!
3) Get into a routine of doing it - once you're in a routine it's easier to just keep doing it when the going gets tough.
4) Try to make it part of your day, for example, I commute by bike. You could get on a bus/train that stops say 30min walk from work, or park 30min walk away from work, then at the end of the day you HAVE to walk back. If you have little ones, promise to take them for a walk in the park - you KNOW they aren't going to let you off.
5) Find something you enjoy. No seriously. If you can find something you like doing, it's not such a chore. For e.g. I don't like running, just doesn't work for me. But I like cycling, so that's what I do. Get creative, dancing to music, digging a trench, rock climbing, ice skating, playing chasings with the dog.....
6) Join a team sport that means you have a commitment to be somewhere at a certain time (I actually work better without commitments, but for many people the commitment keeps them in line).
7) Have a personal trainer or good friend and tell them to be as hard as hell on you. Give them your mobile number and tell them to call you 30min before a session and yell at you if the excuse is anything less than "I'm in hospital and have a broken spine". The "tired" excuse will just about necessitate them turning up and literally dragging you on to a treadmill, tying you to the rail and turning it on 100% fast so you HAVE to run.
8 ) Set up a rewards system, you do exercise today you get a star. 10 (whatever) gold stars, you get a massage, or a movie, or a new skirt...
9) GET ENOUGH REST! If you're always tired, are you sleeping well enough? Sleep is known to be a factor in weight gain/loss. You need (on average) 8 hours per night. And no, sorry, but "catching up" on weekends doesn't work.
10) Take a good hard look in the mirror, and list all the reasons you're doing this. Put it next to the location you normally make excuses in (probably the couch in front of the telly?), look at it and don't even sit down in that spot, get your bum moving.
35kg lost. (November 2005 - October 2006)
15kg gained again (as at October 2010).
Back to the drawing board - Let's do this thing!
"You can't change the winds, but you can change the sails"
"Reach out and take control of what lands in your lap"