What is likely to happen at my baptism?
We can have a practice dry run on the Friday before.
If you are really terrified of going under, then you can have water poured upon your head. That’s why we prefer to call it believer’s baptism more than baptism by immersion. (It is possible they didn’t have enough water to baptise everyone by immersion in Jerusalem, but we read clearly of Philip and Jesus coming up out of the water.