Hi Paradox,
Welcome to the forum! FWIW, my advice is #1) listen to the more experienced guys on the forum, they won't steer ya wrong.
#2) try to get as acquainted as possible with your particular muzzleloader so you know its capabilities. Get a good powder measure, lube for patches(BoreButter comes to mind), patches, and some balls. The patches come in different thicknesses.
#3)Don't use those pellet type powders. DO use black powder such as Goex & Swiss. These are brand names,but not the only ones. The pellet type powder is for..........inlines.
#4)The Renegade most likely has a 1 in 48" twist which is a compromise twist. It will shoot PRB's (patched roundball) ok, and it will also do ok with a minie' style conical(unpatched). However, this twist is way too slow for sabots. Sabots are used with barrels that have a 1 in 28" twist.
The balls for a 50cal are usually somewhere around .490" to .495", but they also have .480" too depending how loose or tight it is from the factory. Some companies barrels vary alot while others have much better quality control. This just a ballpark guess to get you started.
Some of the other guys might tell ya what their pet load is to give you a good starting point, OR it just might be the load your rifle loves!
You can clean the critter with hot soapy water with a patch on your ramrod. After its clean make sure its dry.
One word of caution: DO NOT UNDER ANY CIRCUMSTANCES LOAD YOUR RIFLE RIGHT FROM THE POWDER CONTAINER that the powder came in!!!
Get in the habit of loading from a much smaller container so if a spark was to hit the powder it won't be terrible.
Some companies have a plastic container that holds a BALL, Percussion cap, and 1 charge of powder. This are easy & safe to use. Thompson-Center still makes then I believe.
Well, Paradox, these are the bare basics. There is more to it but I'm sure the other members will fill ya in on more detail!
Now go enjoy yer rifle!
Martin