help on learning program

[hoopty388]

I have a freind with alot of design experience, and uses thing like corel and photoshop. when i told him I was going to need one, he recomended gimp, since it is free, there are lots tutorials, and easy for me to learn (his words). after learning this one I can move up to photoshop etc.

I am starting to learn it, but this is all french to me..I do have a couple questions.....and please remember i am a newbie and these may seem like silly questions, but im trying.to let you know I am not doing shirts at this time, so i went with a 3d...I will mostly do phone cases, plates and coffee mugs. I am not trying to work on the design end at this time, but merely trying to do sizing and lining things up.

Question #1: are there patterns for phones, plates etc, or do you just measure the size and go with that.

question #2: when i set up the program to be 3.5 inches, it actually prints closer to 3.25...am i doing something wrong