I usually just watch my horses the first day, When I seem them looking for water, ( I leave a empty tank near the autowater) I show the horse. Press the paddle and fill he bowl, lead the horse to the water. He will figure it out from there.
They'll figure it out on their own and by observing other horses On the other hand, it never hurts to show him yourself and splash a little of the water around for a second or two so they perhaps pick up the general idea easier.
I always put a bucket out in the paddock next to the waterer until I see the horse drinking from the waterer.
I have Nelsons, so nothing to push down; the new horse watches the old ones and USUALLY figures it out.
However, my TB took a good week to figure it out -- he got the hang of drinking all right, but when the waterer would start to refill he would leap back in horror. So I kept the bucket going until he drank quietly. I don't think you ever want a horse to get thirsty . . . even with buckets they do figure it out eventually.
They figure it out. I recall when I moved my horse from self-care to the Horsey Hilton, and he had been on the trailer for 4 hours, we put him in the stall, he found the Nelson waterer and drank, but when it started the refill process it scared him and he plastered himself against the far wall and snorted at it, giving us all a good laugh. Probably mean of us to laugh at his expense, but it was comical. We didn't give him a bucket, and I don't recall how long it took him to figure it all out, but probably less than an hour.
There are friends and faces that may be forgotten, but there are horses that never will be. - Andy Adams