The conventional method is to use the mechanical Lubrisizer which sizes the bullet to the desired diameter, usually groove diameter +.001", .452" for .45ACP, and injects lubricant into the bullet's lube groove(s) in one operation. Lyman, RCBS, and SAECO make them. $125 and up. See your Lyman 47th manual for more information. You do have a Lyman manual, don't you?
For considerably less money, Lee makes a bullet sizing die for use in the loading press. They sell a liquid bullet lube to coat the sized bullets with by dip or dribble. Let dry before loading.
For minimum investment, Lee makes Tumble Lube bullet molds which cast a bullet close enough to barrel groove diameter not to need sizing, and many small lube grooves to retain dip lube.
I have used dip lube when absoulutely required to and it is slow and messy. The lubrisizer is the way to go if you plan to cast a lot of bullets. I mostly buy commercial cast bullets and don't have to worry about which alloy and lube to use or spend the time over a hot lead pot.
If you like making everything you use, and maybe have a cheap source of lead (wheelweights will do for pistol bullets) it is a good extension of reloading as a hobby instead of just a source of ammo.