With regards to watering dry out your pot till you see your plants just just starting to droop then feel the weight of the pot and get familiar with this weight then water thoroughly (Some runoff) and get familiar with this weight that way you will know when it is time to water. In bigger pots its best to water the soil thoroughly then left to dry completely. That way you insure all parts of the soil get water meaning the roots can grow in all parts of the pot.
Hope this helps.