bonus... how should I do them?

I am in need of ideas for bonus’s for my managment. I have 4 managers, I am not one of them. I do mostly marketing and developement. we have been running a 37% product cost and a 25 - 27% labor cost. I would like to get them down to about 50% combined. I was thinking of splitting the difference between were we are at and were we would like to be based on hours managed. What ways have you guys and gals used for managerial modivation. Thanks.

50% may be unrealistic, and keeping quality up
I think Big Dave Ostrander used to go for 56% and gave bonuses based on anything under that,
with food and labor cost, that figure may be a little higher today
his figures were from 7 or 8 years ago
your’e at 63% combined now, maybe start at 61% and adjust over time,