Mining is one of the harder skills to level up but i have increased the xp rate.
To start mining you need to go to the barbarian place south of edgville.
When you arrive there you should have a pickaxe. You can use a runepickaxe at any level.
1) go to barbarian place and mine the ore that you want providing you have the correct level. If the ore explodes then you will have to wait 10 seconds before you can move to start mining again,