If you are getting ready for your first show, dbol and test or test and deca would not be ideal. In fact, there is a good chance you'll look much worse, running them into the show, vs just going in natural. 

You also mentioned "step on stage or get started". Not sure if you mean, get started on making gains, to eventually diet for a show? Thats the feeling I get and if this is the case, lets take a look at everything else first. 18 is super young for gear. You can shut down your natural test production (leaving you unable to have sex or reproduce) and there is a chance that the increased estrogen will stunt your growth. And understand that Steroids are just a tool that work to maximize your diet and training program. At 18, you can't have trained and dieted long enough to know what works. At best, you have been able to get some good beginner gains, which doesn't really take much understanding of your body. For a new guy, all it takes is going in the gym, banging our reps and eating and you'll gain 15 lbs in the first year. There will come a time that no matter what you do, you wont be able to make progress. You want to get a little closer to that point before you start. At 5'5, 201 lbs, I'm going to guess that you have a decent amount of body fat. That tells me that your diet needs work. Remember that even if you ran the cycle of a Mr O, steroids will only help build muscle. In order to get stage lean, you need to be able to diet the fat off. There are many guys at the gym who never understand that. They just keep "bulking up" and never get shredded. It's a shame really. Fat burners will help, but they only will add an extra 5% to a diet that is already in order and help to push it that much further. 

If your body fat is above 10%, your first goal should be to get it down. I'm going to give you a couple of basics to follow and from there, you are going to need to do reading and research as to how to make this happen. I'd suggest you go to the Project Get Shredded section of the web site and look at the diets I used with those guys. That will give you a basic understanding and show the progress and changes we made each wk. Shoot a front and back pic this week. Then get to work. Report back to me here in 6 wks with your original pics as well as your new pics. Post them up in a new question and we'll see how you're doing. 

Here are things you must do :

eat 200g protein per day, mostly from solid whole foods, chicken, fish, ect

Fats will need to be under 100g, almonds, Natural peanut butter, olive oil

Carbs, start at 125g ED and then adjust down as needed, brown rice, oatmal, sweet potato

Split these macros up so that you are eating a protein, a carb and a fat for each meal, eating 5-6 times a day

Do 30 min of cardio

If you find that you are not losing fat after a couple of wks, reduce the carbs. 

Get ahold of me in 6 wks, here in a new question and lets compare your pics from this wk and 6 wks from now. Either way, if you insist on using gear, or are willing to do it naturally, this is all part of what you would need to do. Looking forward to seeing how you do!