Please tell me how to overclock/underclock my AMD PC?

I don't care if my pc is not able tell me how to OVER/Underclock it i really just want to underclock it just a tad bit.
AMD a4-6210 APU AMD RADEON r3 Graphics chipset AMD K16 IMC Model Larne CRB manufacture LENOVO SOUTH BRIDGE AMD KABini FCH please idc if its dangerous just tell me some way to use it for this pc

Read more: Please tell me how to overclock/underclock my AMD PC?