The filters suggested by Lee will give you the best result but I would suggest that you start with the green filter to establish the correct exposure for the highlight and do the blue filter second to determine the contrast and tonality for the whole print. If you start the blue you will see a contrast in the testthat is not possible to maintain for as soon as you lay soft filtration on you will reduce the contrast. I prefer this way for I think of it as building the contrast. Perhaps the best appraoch would be to try both ways to see which works best for you for neither is wrong.