So I'm pretty good with Soraka, but I wanna get good with a mage, so I picked Ryze since I figured he is the easiest. I've tried different builds with him but I keep dying a lot and I can't seem to do much damage to the enemy. Are there any items that I can get to help prevent me from dying so much? And are there any playstyle tips as well?

Build mana and health items. Frozen heart, Rylais, Rod of ages, and Manamura are all really good poicks on him

As a dedicated mid, I think I can help you.

Through my experience playing mid almost every game, the most important things are (in order): XP, harrass, turret, kills. Note that this may differ from player to player. As a mage, you need to generally build based on ability power (not sure about Ryze cause I haven't played him). I usually get boots and 3 pots and then 2 Doran's rings, then rush a deathcap for that damage boost. As a ranged mid, your playstyle early game should be to CS and harrass as much as possible, this puts pressure onto your opponent knowing that they have lower health than you. Make sure you conserve your mana and only harrass when youre waiting for a last hit or if they get to close.

As a mid, my playstyle is actually very aggressive mid game if I outlane my opponent. Mids tend to fall late game, so I lower the aggression and just sit back and deal damage while not getting focused. Remember, you dont want to rush in to fights you cant win, always predict the result before you go into a fight and base your decisions off of that.

Know your champ, this is very important and might need expirementing. Know how much damage they deal, what champions you suck/excel against, and the limits of your champ and how you do in certain situations.

Pick a champ based on your playstyle. I usually love to get fed early to mid game and I'm all for damage and no safety. And coincidentially, Ziggs perfectly suites my
playstyle with his high risk/high reward abilities.

So all in all, its about knowing what to do in certain situations. You WILL make mistakes, so try to identify them and immediately fix. Just dont try too hard to not make them, cause thats how you learn.

Hope I helped :)

Two things about Ryze:

First, you have to combo your abilities properly. Generally you want to use a combo something like QWQEQRQWQEQ, if possible. You do more damage than just going QWER.

Second, Ryze doesn't build AP. Get an early Tear of the goddess, go sorcs (or mercs if you need to stay alive), RoA, Frozen Heart, Manamune (muramana is godly on Ryze), then more mana items - BV, something like that.

Ryze is a shorter range caster with sustained, late game damage. He's more akin to an ADC-type mage than a burst caster like Veigar.

You need the basics, first, though! Get your CS (creep score) to a reasonable level. Try for 200 CS by 20 minutes in every game. That's very good - 150 is acceptable. Don't forget wards. Wards are VERY important. They can win you games.

After that, work on your positioning and knowing how much damage you can do.

Thanks for the help guys! I ended up finding a build on here that works wonders! I'm doing much better! ^_^