I had a figure 8 leather halter on my foal every single day since she was born. Put it on daily when I get there and then take it off when I leave. I am now working on walking her on lead with it, but I never pull her, their necks can be injured very easily, so it's slow work at this time. She is now 7 weeks old. She has had 4 days since being born that her halter wasn't put on her.
It's a leather figure 8 halter I think I ordered online, they are much better with pressure points and release of pressure. Look them up