1. Take photos early morning or night as there as less shadows
2. Always make sure your battery is recharged (or you have spare batteries) so your camera doesnt suddenly die on you at the worst possible moment
3. Get closer - if you can't get closer zoom in further, if you can't zoom in get closer
4. Learn to use the histogram to adjust settings and get a good exposure.
5. take the lens cap off doofus!
6. Check that your camera is not set to auto ISO,(unless you definitely want it to be) learned this the hard way.... as have many others, I expect.