I want to make a All Dragon deck! Please help! Thank you?

I recommend using Cost Down- this will make bringing out your higher-leveled monsters easier to do- definitely helpful if you are attempting to summon a monster like Gandora The Dragon Of Destruction if you do not have the required tribute. Call Of The Haunted is also a helpful trap, Magic Jammer is also recommended. You could use both Dimensional Prison and Sakuretsu Armor- each are very useful in terms of defense.