Losing weight…. Tips? (: Thanks!?

Jello Asked: Losing weight…. Tips? (: Thanks!?

So, Let me start off with this. It' s summer, right? Right. I'm about 30 – 40 pounds overweight. I'm hoping to lose a good amount before we go back to school, August 27th. But I'm hoping maybe before, for school shopping. Clothes. Me and my friend made a bet to see who would win. I only drink water as of Sunday, and i drink about 2 – 4 bottles a day. I attend summer camp 5 days a week, and do Karate (3x), Hip Hop, and Tumbling for 45 minutes each. I also have been cutting down my portions, eating healthy, less food, and no food after 7pm. As for excersise, im super busy, so i try to do this daily when I can:
Stretches
20+ Pushups
100 Starjumps
60 Jumping Jacks
20 Situps
1 minute fun (Crazy Dance,? Takes the energy out of me, haha c: )
10 minute jog on spot

As the weeks go by, ill increase it.
Now, I'm wondering, will this get me to my goal on time? I really need to lose it, for several reasons. I'm getting sick of being overweight. I know I'm beautiful, I know god made me who I am, but just my weight is killing me. Like i said, i don't have a lot of time on my hands, I have summer camp, then The Keys in two weeks.
Any tips? Please help (:
Yes, I know it may sound impossible to do, but I KNOW I can do it. I pray to God every night and I know he will help me too. I'm just wondering, is the diet I have enough? How much would I lose?
Thanks <3