Mining is simple but time consuming like many skills.
*To mine first tele to PK zone, from here you want to head south until you have reached barbarian village. No this is not the mining spot. From here head over the east bridge towards varrok. Keep heading east till you hit the varrock wall. From here head south to the mining spot by the Champions guild. The mining spot is southwest varrock.
What to do:
*Be sure to have the pickaxe equipped. Mine the light grey rock which is tin until you reach 15, then mine the dark brown one which is iron until 20, from there mine silver ore which is a shade of grey but it looks more white than grey. Good luck I hope this guide helps you