I don't trade much either but I use Bet trader evolution when I do. I like the full version but it also has a free version which has a few less features and doesn't update as often as the paid version. The good thing is that you can buy days rather than a full subscription, so you could buy say 15 days and then just use them as and when you wish. This would then give you access to training mode which lets you trade almost as if it were real but without actually using real money. With this feature you can test some ideas in a realistic environment.
I also used Bet Angel I think it's pretty similar to bet-trader, they both have free versions and paid for versions and both use the ladder idea which makes trading much easier. I don't think you could really expect to be a real trader without some software as they just update so much faster and give you an edge over anyone who is just using betfair.
Try them both and the one Sharpeshooter suggested, you can try them for free then take your pick.