Mage for low levels

When training mage never wear armour that is made of metal or dragon hide (Unless you are using curse but we will go into this later) this will ensure you get the maximum xp per rune.
From the very low level you can speak to the mage tutor near Lumbridge general store and he will give you some runes if you don't have any on you or in your bank, if you have some drop them on the floor ask for some more then pick them up again.
Once you have your runes cast whatever you can cast on the goblins just across the bridge from the Lumbridge guides, wear the best mage armour you can get, even a wizard hat will help very slightly, mage them over the fence so you don't get hurt, when you kill a goblin collect his drop and bury his bones, sell anything they drop to the general store, you can go back and get runes every 30 minutes so train a bit of melee when you are waiting.
Unless you want to be a mage pure I suggest you get your combat level up a bit, this can be done easily by attacking the rats by the castle or the men outside, pick up everything they drop and sell in the general store to get yourself some cash, if you are p2p then collect their herbs and bank to sell to players or later, men and women often drop ranaars current street price 7k each.
When you get a combat level of 41 then you have the chance of some very good mage xp, go to the wizards circle near Varrock south gate, attack the level 7 dark wizards there, do not wear metal armour, wear leather range gear and use the best melee weapon you can use, when you kill these wizards they drop a lot of runes, use the runes on the other wizards as you get them so you are effectively killing wizards getting runes as drops and using their own runes back on them as spells.
Kill the level 7 wizards here to get good rune drops, watch out for the level 20's thay can hurt.
The reason I suggest a combat level of 41 is because there are level 20 wizards there and they are aggressive and will attack anyone under that level, because they mage they can get you for a long way, I have seen many a new player losing their items to these bad tempered wizards.
This is a busy spot and many players leave the bones on the floor run around pick up all the bones and bury them this will help your prayer fly up.
If you start to get low on health run through Varrock gate and head immediately east there is a cabbage patch there pick the cabbages and eat till you are at full health then take a few more so you can fight for longer.
The runes you can not use put in the bank until you can use them or if you prefer sell them to players.
Use this method for as long as you like it is good free mage xp and if you sell the runes you can even make some money.
I will add an intermediate mage report at a later date.