Build a block or iron (use 9 smelted iron ingots).
place block of iron. now all tools except the sword, lighter and shears will repair themselves when you right click on this "anvil". You must have materials in inventory to be used in the repair. Repairing higher level tools requires higher level repair skills.. ex: you need level 70 to repair diamond tools. You may want to use some wood, stone and iron tools for a bit, repairing them as required to build up skillups towards repairing diamond tools.