Equal volumes of powder and shot. Around an ounce of shot would work fine. Wasp paper, newspaper, brown wrapping paper will all work for wadding, if you do not have conventional fiber/card/cork wads. These can be made with a wadcutter and drill press. I microwave cork wads in Crisco, to saturate them with lube.
If you are at a range, a dowel that just fits the bore is more convenient for loading than the under barrel rod.
The over powder wad must be seated firmly. Overshot wad must keep shot in place. After one shot, decap the unfired barrel and make sure the charge hasn't shifted forward under recoil. Don't have to do this every time, be satisified your second load isn't moving.
Get a capper. Beats fishing the caps out of the tip one at a time.
I pour powder from a horn into a measure; not directly from the horn into the bore. Have a measuring shot flask.
It is very convenient to make up little paper cartridges of powder and shot. Use brown wrapping paper, like that the National Geographic comes in. Glue into tubes around a form, glue one end shut, fold over the open end. Cartridge paper goes down the barrel as wadding. \national Geographic would like to think their wrappers are being recycled/reused. If you use something like soft paper towel for wadding, make sure you aren't spreading smouldering embers.
If you fire only one barrel, NEVER reload it without removing the cap from the unfired barrel.