Making your own leaders?

[Delverdude]

I have made my own leaders for as long as I can remember fishing, however I usually just tie a 4 foot piece of heavy mono, 30ish pound, then I tie onto that another 4-5 feet of whatever size tippet I think I need. I now want to start making my own tapered leaders, but I am not sure how many sizes of line to use, or how large of a size jump I can do. I am mostly wondering about leaders for trout on the dry, but anything about a bull trout/walleye/pike leader would greatly be appreciated.

Thanks in Advance