a bosel is harsh though. I would switch him over w/ a snaffle using two reigns. Cross the reigns and then hold them about 8 inches apart and when you ask for a turn, use your leg and your seat, take the reigns and move both hands towards the direction you want to go, stop when the reign touches the neck, dont cross the neck w/ your outside hand. By doing this, you are teaching neck reigning. You can move on to a port bit as well but it would probably be easier on you if you arleady have neck reigning.
"Be a best friend, tell the truth, and overuse I love you
Go to work, do your best, don't outsmart your common sense
Never let your prayin knees get lazy
And love like crazy"