@markus_zhang
Since the original Diablo, my favourite class has been Sorcerer. I've played it more than anything else. I think I can give you a few tips (some of them I actually learned from Wendigo, lol; hi there, Wendigo!)
1-All you attribute points should go to Magic. ALL. If you are not doing this since the beginning, playing with Sorc will be harder. You should rely on your gear (specially rings and amulet, which only require clvl -character level- to be equipped) in order to have enough Stenght to use a good armor, belt and helmet.
2-I have never seen a Sorc do better with Shield and Sword than with a good Staff.
3-I beat Hell Difficulty with my Sorc. Some bosses were tough, but Diablo was easy. I was level 43 when I did it, and I did not need to grind for experience a lot, maybe just a couple levels.
4-I also did not have other chars to help my Sorc. He was my first char. So it is doable, if you play right (Torment Difficulty is hundreds of time harder, and do require support from other chars, unless you wanna spend hundreds of hours grinding with the Sorc by himself).
5-There is a quest that gives +1 for Guardian Spell. There is another quest that gives +1 for Golem spell. You should NOT COMPLETE these quests right away; SAVE THEM up to when you have got these spells on level 12 (or, at least, 11) just by reading books. Then you go back to each difficulty, complete the quests, and get the spells to their maximum level of 15.
5.1-If you don't do this, it will impossible to have the spells maxed out because the books require a stupid amount of Magic.
5.2-If you get the spells to level 11 by reading books and then complete the quests in each of the 4 difficulties, you get them to level 15. BUT if you get them to level 12 by reading books, then you can get them to level 15 by completing the quests in the 3 first difficulties, and you can play on Torment with the spells already on max level.
6-This video shows how Sorc can handle Torment difficulty:
https://www.youtube.com/watch?v=QPV1TIx2Y3s
It is basically what Wendigo sair: Bone Spirit, Meteor, Apocalypse, Golem, Teleport.
But this is still a distant future for you; you can beat Hell Difficulty with Chain Lighting, Guardian, Blizzard, and the proper gear, of course.
Hope I helped! =)