One tip that my mom (an internist) suggested was to take the ibuprofen before the cramps really started. The ibuprofen helps reduce the uterine spasms by an interaction with the hormones that trigger cramps, and it is easier to prevent a muscle from spasming than to get it to relax. Taking the ibuprofen before the pain starts also allows time for the painkilling aspect of the drug to become effective in your system (most medicines take ~30 minutes to enter the bloodstream through the digestive tract.)
Personally, I prefer a long bath followed by a nice nap, but taking a whole day just because you have your period is not socially accepted anymore. (where are menstrual huts when you want them?)I guess the best would be to have the day for the long bath and the nap without the pain, but someone would probably catch on to the scheme.