i got some balloons at the dollar store to practice on...big waste of money....they weren't worth it...just go ahead and get some good balloons...you will be glad you did....believe me, i am not good at this..but it's fun...i just tell them when they ask for something specific and it doesn't turn out right...i just say..."hey, it's a kidney"...or "it's your intestines"...they always laugh when i do that...especially when my twists come undone and make funny shapes...sometimes being perfect isn't as good as being imperfect...at least you get them to laugh....
