Greg Hickok - Hickok45 - had people going with his spoof video on cleaning an AK-47/AK-74. Now he has released the real video below on cleaning an AK.
One thing Greg makes clear in this video is that you are often dealing with corrosive ammo. He refers to using Windex but prefers using Ballistol. I've used Windex myself in the past but anything that dissolve the corrosive salts will work. If I remember correctly, the British had a special funnel for pouring boiling soapy water down the barrels of their Enfield rifles which would work as well.