A few tips for people starting off.
Tips for Starters
First and foremost, Dark Souls is not like other games. You WILL die, and you will die A LOT. It's a game that will hammer you down, and hammer you hard. And because of that, there's no better feeling than beating a boss that you've been having so much trouble with.
Secondly, this game wants you to explore it. You will find very little about the game unless you look and read, most things won't be told to you. You will find goodies and secretes through exploring, and things about the lore too. The game also while is linear in a way, lets you choose what you want to do first. You can choose if you want to fight some bosses early or late.
Don't be afraid to try out new things, but also try not to put your stats randomly. This goes double for Sorcerers and Clerics. Almost all of the damage your spells and miracles do are based of Intelligence and Faith, unlike others who has most of their damage scale with their weapons and gear. So experiment, but also be aware of where you put your stats. And keep in mind that you don't have to farm to beat the game. If you're having trouble with an area, don't think it's because you're not high enough of a level. While this can be the case, you can also beat the entire game level 1 as well. This means you'll pretty much never have to farm unless you want to.
This game also has a lot of replay value, so if you miss something or mess up a quest you can always just make a new character. And you will NEVER do everything in one run, so keep that in mind as well.
As for the combat, this game punishes you for mindless button pressing, and rewards you for paying attention to the enemies and how they attack. Meaning if you go into a fight and just stand still and spam R1 like you would a lot of other games, you'll die. And fast. And if you try healing when ever you want, you will get killed while healing, so pick when you do it at a good time, because the most frustrating thing during a boss fight is going to go heal and getting killed because of it.
Lastly, and most importantly, play how you want. You can turtle up behind a shield, roll through the attacks like a madlad, tank everything and hit everything with a big sword, use a bow or magic, miracles, or pyromancy to shoot from a distance, or mix it up and use magic or pyromancy, or both to get buffs for you and your gear for a bit. You can play however you want which is one of the best parts of this game. So if anyone tells you you're playing wrong, or says you should do X or Y, tell them to bugger off and let you play how you want to.