Without going into too many numbers here is my formula for an economical presentation and what I tell beginners so they don't get discouraged or over consumed with equipment purchases. I use fluorocarbon 9 foot leaders with two sections of fluorocarbon tippet, each 12-36 inches long and the first piece of tippet is one diameter less than the leader and the second piece is one diameter less than the first. Two sections of tippet below the leader allow multiple reties without eating into the leader. Buy three spools of tippet (4,5,6) and keep one each 3x and 4x leader on hand. Your 3x by itself can handle a large mouth bass or your 4x leader with 24 inches of 5x and 36 inches of 6x will give you 14 feet of leader for the most timid trout. The flexibility, lo-visibility, and durability of these 5 items will take you through 4 seasons of fly fishing in PA. Yes, you could buy more and you could use more and this formula leaves out the size 22 and smaller hook. Take the money you save and go fishing a few more times! If you want a lot of details, seek out the Orvis book on leaders, tippets, and Knots by Tom Rosenbauer. It has formulas and tables galore.