Is this effective to lose about 8 pounds?

I need to lose 8 pounds and id like to keep it off, and id like to accomplish this in about a month. heres my plan.. cardio mon-fri for 40 mins, running/walking on an incline every other day, and elliptical the other days, and every other day ill lift light weights for my arms/abs/back, and the other days my legs, and . is it ok to do light weights when trying to lose 8 lbs, or should i lose the 8 lbs before i start to tone by just doing cardio?? i am also doing this in conjunction with an appropriate diet.