The goals I try to set are average related like bowl 180+, or to focus on spares or concentrate with full attention to every ball, get the ball it the pocket after each ball. In one on one games I try to beat the other player eg. they bowl 9 spare then I have to bowl a strike, they bowl 7 I bowl over 7. Although I have found that this works for me it may not work for other people.
,Jordan