How do you get a skillcape on RuneScape?

To get a skill cape you must get 99 in the one of the following skills

Attack:99

Strength:99

Defence:99

Magic:99

Range:99

Prayer:99

Constitution:99

Mining:99

Smithing:99

Herblore:99

Agility:99

Slayer:99

Farming:99

Hunter:99

Construction:99

Summoning:99

Crafting:99

Thieving:99

Firemaking:99

Fishing:99

Cooking:99

Runecrafting:99

Dungeonearing:99 or true skill mastery:120.

Hope this helped :)