Some snakes will happily eat a rodent that is warmed up and just left in their cage, many need you to do the rat/mouse dance with the tongs. I'd start out doing the dance as they are used to live prey then in a few weeks try to just leave it in there.

I have always bought in bags of 25 but I am going to stop - with just one snake to feed each bag lasts over half a year and I am noticing a huge amount of waste/skipped meals towards the end of the sack. I keep them in individual zip locks too so they are sealed as they can get. My advice would be don't buy in bags of more than 10 meals/snake at any one time.

Defrost them inside zip lock bags ina tub of warm water then when thoroughly defrosted stick the bag back in fresh hot water for a few mins to warm them up. The bag means they don't get wet or lose thier scent.