Dissolve 10g Bacto Tryptone, 52g Bacto Yeast extract and 10g NaCl in MilliQ H₂O in 2L flask (if making agar plates, add 15g agar powder). Adjust the volume to a liter and autoclave at 121^oC / 15 lbs for 20mins. Cool the solution and add the appropriate amount of antibiotic prior to use (for agar plates, add antibiotics at 45-60^oC).