I would say don't spray in direct sunlight. Try to do it in a shaded area so the paint doesn't dry as quickly. When paint dries too quickly, you can end up with intercoat delamination, which describes when the paint starts to peel because the gases are produced too quickly and aren't able to properly dry. Also remember to be conscientious of overspray. Take the wind into consideration whenever you're spraying, as it will get onto other surfaces if it is a windy day.