I'm planning on doing a Vampire Assassin play-through. But I need a few tips.

Right now Imma cheat (only a little) and spawn in Shrouded Armor (full set) and increase my enchanting and smithing to 100 with full perks, mainly because those are the only skill trees I really need (from past experience). All other skills wil be brought up normally.

Reason behind the skill increase is because my RP idea is that she is a old former assassin from a Dark Brotherhood down in Cyrodil, she's one of the last few remain and every family member has been the only ones. Her training mainly consisted of enchanting and smithing so she appeared normal.

But I need tips because this is a Mage play-through, use magic to kill enemies. Any tips and suggestions?

I would toss aside the smithing. Mages - you did say mage play-through - worth their magicka likely would not have the time, or need. Enchanting - although not explicitly mentioned - requires an understanding of Mysticism, which was blended into the other schools, although you could imagine you are using glyphs for the sake of role-playing.

Alchemy and Enchanting would be her best choices. They are common enough professions in Tamriel to parry suspicion - in addition to being less resource-dependent - and would fit her line of work.

--Mickles, GunFuMcMickles

Anything else? Cause in earlier trial runs on the xbox I died so many times and often very easily

I do not know the specifics of those situations so I cannot address them in great detail. However, I can say not having smithing at max level - or at any enough high level - makes you easier to kill, more so when you are not using any armor as a mage. These drawbacks are sort of inherent in sound role-playing.

Alchemy and Enchanting alleviates some of the difficulties. You could do a lot of damage with poisoned weapons and give yourself buffers via potions, and enchantments can make you less squishy. Try to remain supplied on potions early on.

I was going to spawn in Dark Brotherhood Armor as my PC's "cannon" armor