So, the first thing is I wouldn't pack a computer. Unless you're a working businessman, I wouldn't pack a computer. There's internet cafes all over the world. You can use them anywhere, and it's not a necessity I think.
The second thing that I wouldn't pack is too many clothes. This is the difficult thing for everybody. You can reuse clothes and there's always places to get your clothes washed so very minimal, very minimal. Don't overpack clothes.
The third thing is I wouldn't pack too many books. People tend to love to pack and carry far too many books. Generally, you can always find books on the road or there's other travelers that you can do book swaps with, or there's little book shops and things and places you buy things. Don't bring too many books. Bring maybe two or one good book you can swap or buy.
The fourth thing that I wouldn't bring is a big towel. A big towel you use once and then it gets wet, and it gets damp and it gets smelly and you put it back in your pack. I would bring a small travel towel. Very small. Rolls up to the size of a sock and dries very quickly. It's very handy.
The fifth thing that I wouldn't bring is too many toiletries, like shampoo or soap or hair gel because these things are ... everyone around the world uses them and you can always buy them somewhere, so I'd buy the little small travel ones, and whenever you need another one.
And the sixth thing that I wouldn't bring if I were you is maybe too much footwear. Generally, unless you're going to different climates, if you're going to do a long trip and it's going to be winter and summer then maybe you need two pairs of shoes but generally I bring only one pair of footwear, and sort of it's good for the area that you're going to and maybe one pair of sandals.