Estimating Yardage for a very long, Long Tail Cast On
Usually knitters estimate that they will need 3 to 4 times the length of the cast on row for a long tail cast on. Most of the time you can figure out the cast on edge length by the gauge indicated in the pattern or by the finished schematics. Somtimes this guessing leaves you short (and you have to start over) or with a very long (and wasteful) tail. When casting on numerous stitches for afghans or ruffles or scarves knit horizontally, there is a much better way to go: Use two balls of yarn, or the inside and outside yarn ends from one skein. Hold yarn ends together and make a slip knot and place it on your needle. Hold the two strands of yarn from the slip knot in your left hand as you would for a regular long tail cast on and begin. Your will not run out of a tail for your cast on and you cannot run short! After casting on the needed number of stitches simply snip one of the ends of yarn leaving an ample tail to weave in later and begin kntting away. When you come back to the double stranded slip knot you can knit them as one stitch. Easy.
Three Needle Joining Technique

I used this technique to add ruffles to "Ruffles" the sweater on my For Pets page. Lay the needles with the right sides of your work on top of one another. Hold the two needles in your left hand with their points facing right. Take a third needle in your right hand and insert it knitwise into the first stitch on the front neddle and likewise into the first stitch on the back needle. Knit the two stitches together and continue across the row.
Lifelines

Lifelines are used often in lace knitting where ripping back to correct a mistake and getting stitiches back on the needles is especially difficult. I also use lifelines when I am designing to allow me to rip back easily when necessary. It is easy to do and a huge time saver. Thread a tapestry needle with a smooth contrasting yarn of lighter weight than the yarn used in your project and slide it through the stitches on your needle, running it just below the needle. Leave generous ends hanging out each side of your project. Then knit on normally being careful not to knit the lifeline. Later if you make a mistake (or don't care for the direction your knitting is taking) take the stitches off your knitting needle and rip back. You won't be able to rip further back than the life line. It will hold all your stitches ready to easily picked up so you can begin again.
Alternative 'Make One'

When a pattern instructs m1(make one) unless otherwise noted they mean to create a new stitch by picking up the horizontal strand of yarn that lies between the stitch just knitted and the next stitch on the left hand needle. You would put the strand on the left hand needle and knit it through the back loop to complete the increase. Another method is shown at left. Simply put a backwards loop of yarn on the right hand needle. I find this increase is easier to work than the traditional one when I am working with DPNs and small guages.
weaving in yarn ends
When you are working with multiple yarns like I did for the Plaid Topper on my For Pets page, weaving in all the yarn ends when your project is finished can be very tedious and boring. This technique of weaving in the ends as you go will save your sanity. No yarn needle is requied and you don't even have to stop knitting. When you are ready to change to a different yarn, snip the old yarn leaving a 6-8 inch tail and pick up the new yarn. Put the old yarn's tail over your working yarn and knit/purl the next stitch and repeat this for a few stitches. All you have to do when you get to the end of your project is snip all the tails.
cable cast on
To begin, I have no idea why this method is called the cable cast on since it has nothing to do with cables or a cable needle. It is however, simple to do and results in a somewhat firmer cast on edge than, for instance, the long tail cast on.
To get started, make a slip know as you normally would and place it on your left hand needle. To form the second stitch, use your right hand needle to slip into the slip knot's loop from front to back, wrap the yarn around the right hand needle and pull the new loop through, just like when making a knit stitch. Now transfer this stitch to the left hand needle by slipping the left hand needle into the front of the stitch on the right hand needle. Keep your stitch tension relaxed (don't pull tightly on the stitch just made).
Now you are ready to start the cable method. To make the second and subsequent cast on stitches, insert the right hand needle in between the two stitches on the left hand needle, loop the yarn around the right hand needle as if to make a knit stitch, pull the loop back through and transfer it to the left hand needle as you did above. Continue in this fashion until you have all the cast on stitches you need.
With this method you first row will be a right side row.
To get started, make a slip know as you normally would and place it on your left hand needle. To form the second stitch, use your right hand needle to slip into the slip knot's loop from front to back, wrap the yarn around the right hand needle and pull the new loop through, just like when making a knit stitch. Now transfer this stitch to the left hand needle by slipping the left hand needle into the front of the stitch on the right hand needle. Keep your stitch tension relaxed (don't pull tightly on the stitch just made).
Now you are ready to start the cable method. To make the second and subsequent cast on stitches, insert the right hand needle in between the two stitches on the left hand needle, loop the yarn around the right hand needle as if to make a knit stitch, pull the loop back through and transfer it to the left hand needle as you did above. Continue in this fashion until you have all the cast on stitches you need.
With this method you first row will be a right side row.