Getting a horse to frame requires more leg than hand. I'd say 80% leg, 20% hand. You have to "push" your horse into the bridle. This way they are driving with their hind end. If you use too much hand, the horse is put into a forced frame, and this can cause damage over time. Tickle the inside rein while applying light, constant pressure on the outside rein. Just play around with it because all horses respond differently.
In my experience half halts work really well for this, along with circles. Just lightly 'play' with your outside reign but still encourage a good stride.
Getting a horse on the bit is much more than 'getting their head down'. You want your horse to be going forward from your leg in a relaxed and rhythmic way. Keep your outside contact steady and ask your horse to soften with your inside hand. Lots of transitions will help get your horse underneath himself, helping him to use his back and to round. Circles too, using your inside leg to your outside hand to control. You want your horse to step underneath himself, lift its back and stretch forward into your contact, seeking the bit. Trotting poles are good for this :) It won't happen over night and you will get bits of it here and there but with correct work it will come together:)