Here is a good LINK
going in detail of how to lose weight for fighting and below is my take on it.
As far as losing fat weight/long term weight loss I recommend cutting your caloric intake per day by about 500 calories and start eating 6-7 smaller meals a day.
I also recommend cutting out all fast food, soda, desserts and junk food in general. Try to eat one serving of fruits or vegetables with each smaller meal.
If dieting is hard for you, like it is for me, you can have one cheat meal a week. Eat whatever you want for that one meal.(just avoid buffets). Only do this once a week otherwise you are not really dieting.
If the weigh-ins are the day before the event you can easily cut the last 10-15 pounds 2 days before weigh-ins. The only thing I do not agree with in the article is the comment about the make-up remover. I personally use Albolene (which is a mix of mineral oils and Vaseline) and it works great and I have had no negative side effects from using it. Plus Albolene actually recommends using the it for weight loss.
I hope this helps and if you have any additional questions feel free to ask me.