Hill County Texas
I have attached a great article written by our Extension horticulture specialist Joe Masabni in the link above. It discusses leaf cupping and twisting. There are multiple cause of leaf twisting.
As far as watering. You should water with a slow rate of water at the ground or soil level, dont use a sprinkler or overhead water source, that will only cause problems. This time of year I like to water tomatoes 2-3 times a week. Water slow and deep. Watering to a depth of 6-8 inches by the plant is recommended. You can push a small rod into the ground to measure how deep you are watering.