i was always taught to get your horse forward and moving first and it was hard for me because my horse was already so speedy so it was hard to keep it together but when i got him forward i was taught to “massage the tongue” it sounds weird but it’s basically half halting both the inside and outside rein but you need contact with the outside rein and to soften the inside to keep him there and when you massage the tongue enough to where they will come done that’s when you soften the inside while keeping contact with the outside!
Find yourself a new trainer. A horse being on the bit is a lot more than just pulling its head down and kicking on. A horse that's on the bit is coming up through it's hind end, over its back and into your hands. It's the pinnacle of power, strength and balance. It takes years of training.
To be honest, I'm actually a little bit horrified that your trainer is insisting you just put your horse there. I can only assume they think something like Rolkur is being on the bit, where you pull the head in. Head position happens naturally when everything else is right.
You should never feel scared to ask your trainer anything.
In order to have the contact in the front, you need impulsion. To gain impulsion, you can do some half halts( outside rein and inside leg). This makes your horse respect your legs and hands. Hope this helps!
First of all start off by opening your reins and squeeze them with your legs to bring through the hind quarters ! While doing this do not wiggle or move your hands or you’ll interrupt your horses balance just keep your hands super still and open and push with your seat and feet