There is something wrong if your memory card is lasting for months without becoming full. Essentially the problem is that you’re not experimenting enough.

Ideally your memory card should have 50 pictures of the same subject, all of them bad. These 50 photos, even though they are bad, prove that you are not afraid to try out different exposures or different techniques. And then, hopefully, there should always be one good picture. This one picture proves that you are not completely incompetent.

The general rule is that it takes approximately 10 frames to get one good picture of one person. If you are doing group photos you will need to hold down the shutter release button and take loads of photos, hoping to finally get a good one of the entire group. You want to take pictures from different angles, different heights, flash on, flash off, etc.

My recommendation: buy a stack of 2 GB SD cards and challenge yourself to fill them up!