Kinda new to this..

I've tried this before and i was into it for a few weeks then i just stopped. My dad owns a diner, and I work there 6 days a week. its SO hard to lose weight when i eat breakfast & lunch there almost everyday! I try to eat healthy by staying away from fries, bread.. all the yummy stuff but my sister is getting married at the end of October and Im SQUEEEZING into my bridesmaid dress. My mom says I need to lose at least 10 lbs by her wedding so she can fix my dress up. I've been looking up some healthy recipes.. & I love trying new things, eating healthy isn't my worry... working out is. I don't know many good exercises & when I get out of work at 3..I'm so tired! I need ideas on how to boost my energy so I don't want to be a lump when I get home from work. Any help? Add me as a friend as well! Thanks!