You have to do it through diet/cardio and possible fluids manipulation ( not diuretics...). Clean your diet more and if it's not working add cardio.
You cannot stay in 69 class anyway for rest of your life, you're so young and will continue to develop considerably muscle wise.
Drop the plans to use gear atm.
You do yourself a huge favor. Nothing will magically happen to your bf level. It's common misconception you get magically cut like pro mr olympia, but you already know this i bet.
Train with rubber bands ( one seriously good way to develop explosiveness / strength ) for any lift, add slow eccentrics. Most of all give yourself time to develop. Those Ed Coen's who won IPF championships at age of 21 are few cases in over 7.3 billion people.
All the best luck!