I start my seeds in 2" cubes. Once they sprout I immediately put that in a 5 gallon pail of soil that has been watered till runoff.
For sure the next week I don't water it at all, the 2nd week I lightly mist the top of the soil if it looks bone dry.
Every morning I heft the container slightly and judge its weight relative to what the dry soil weighed.
When I do water, its the outside edge of the container, never the center. I'll add a little, and come back in 20 minutes and add more.
The finger method works till the soil gets so rootbound that you have no hope of getting a finger in it, about when bloom starts.