After having played one, and after reading numerous articles on them, I've found the perfect mix for a battlemage.

Race - Breton

They have increased skills in

• Healing+10
  
• Mysticism+10
  
• Illusion+5
  
• Destruction+5
  
• Alchemy+5
  
• Alteration+5

Some wont be used but Hey, who cares.

Birthsign
The Mage is the best choice.

The Atronach is not good, for it has the most magicka, but stunted magicka is horrible.
And the Apprentice's magic weakness is horrible. Because generally, mage-like classes are usually not good in the "High Health" category. Thereby, if a character hits you with a medium damaging spell, for 20 damage, if you're an apprentice, it's 40, that's just pitiful.

Thereby the Mage is the best choice. It's a balanced birthsign.

Attributes
Strength and Intelligence

Major Skills

• Destruction
  
• Conjuration
  
• Heavy Armor
  
• Illusion/Alchemy (I prefer Illusion)
  
• Blade/Blunt (Or both, depending on what you prefer)
  
• Restoration
  
• Alteration

The first thing I did was conquer the Mages Guild, then once I got the spell creation, find a detect life spell, create one with the lowest possible settings, for something like 10 gold, that costs 1 mana to cast, use this when walking around or such to increase your levels dramatically in Mysticism.
After creating that mock spell, I created another spell (Note that these are self targeted unless I state else.) using Bound Dagger, use that, lowest duration possible, one mana point again, and it can simply be cast while walking. Create another spell using Weakness to Elements in destruction tree, again lowest settings possible. Repeat for Illusion, use a custom Light spell, Restoration, use a custom restore health spell, Using a custom shield spell for Alteration is best. If you chose Alchemy, then creating Restore Fatigue potions does the job. Know that the magic experience points are awarded for each cast of the spell, not based on damage done or level.
To get Blade skill up, get a more powerful summon, and repetitively attack it with a dagger, low damage. Remember that the experience for blade is per attack, not how much damage or such, so you want to fastest attacking thing, and do not use power attacks.
After having done Restoration, I recommend you do the restoration training before attempting this, get a mud crap or a rat to attack you, and just stand there healing yourself, they do little damage, and once again, Heavy Armor counts the experience per attack, not the amount of damage. The reason your restoration skill will be good is so you don't have to go rest. Also, if you're wearing regular armor, this should be easy,

After doing that I recommend you go conquer the fighters guild real fast, shouldn't be difficult.

Also, once you get the money for it, I recommend that you enchant your weapon with enchants to make it awesome, and I recommend you get Azuras Star as soon as possible (Reusable grand soul gem) because you'll need it for refilling the weapon you create, and I usually make sure to put a soul trap spell on it, that way you can just refill it after. For your armor, I recommend getting at least the + 50 mana enchant on every piece. Which could be Brusef Amelions armor, or an imperial battlemages armor. Either or. I recommend you max out your magicka.

To be continued tomorrow.

Completely disagree. Just raid an Ayleid ruin or two for Welkynd Stones and you'll be good to go. Plus, making Restore Magicka potions with alchemy is very easy, and you can also visit Ayleid wells all around Cyrodiil for instant magicka restoration. I also think it's quite fun to play under the sign of the Atronach. It requires you to be careful with throwing spells around and encourages thinking of strategies before jumping into a fight.

First I trained my Restoration like that. Good training. But now I prefer to create a low spell of damage health on myself and repeatedly heal me with a low restoration health. Same for destruction training: low spell of damage fatigue. Anyway thanks for your good advices.