Trust Me you're not going to get Bodybuilders Arms, for that you need Perfect Genetics, Diet, Rest and of course "Supplements". Here are a few tips Work your Triceps just as much as your Biceps, if not more. Triceps take up roughly 2/3 of your Arm Muscles. Dips, Tricep Kickbacks with the Dumbells are an ok excerise (You won't be able to move much weight with this excercise though so start Light) , Would be much better to do Dips, Close Grip Bench Press (Need a Barbell + Bench for this). For Biceps just do Standing/Seated Dumbell Curls. Also you could do them on an inclined surface to Isolate the Bicep more