You may want to consider looking at some of the literature by Larry Wise. He has done some significant research, writing and coaching on just this topic on the mental focus aspects of archery. Take a look at: https://larrywise.com/planning-to-peak-in-archery-page/
He is also currently doing some cool research and experiments to better understand Quiet Eye theory that will fold in to some of what he talks about there. Probably another publication coming out about that and eventually.