The first stitch of your cast-on row is usually formed by making a slipknot. To do this, first fold the working yarn in front of the tail end to form a circle.
Using a knitting needle (or your fingers), bring the working yarn through the circle, from back to front, to form a loop.
Place the loop onto a needle and draw up the tail to tighten the knot, being careful not to pull through the tail yarn. The loop should be snug but not tight.
The knitted or two-needle cast-on
Place needle with slipknot in LH. Hold empty needle and yarn in RH. Insert RH needle into front of slipknot
With RH, take working yarn clockwise around the back of the RH needle.
Bring the RH needle towards you, drawing the loop of working yarn on RH needle through slipknot.
Transfer yarn to LH needle by inserting tip of LH needle into front of loop on RH needle
Slide RH needle out of loop. RH needle is empty. Two loops on LH needle
Rep steps 1-6, inserting RH needle front to back into last st worked
A simple cast-on worked on one needle. Moderately firm with limited elasticity but smooth and neat. Work the first row as a purl for the smoothest finish.
Measure a length of yarn approximately three times the length of the cast-on edge. Make a slipknot, leaving a long tail of yarn. Place slipknot on needle and draw up snugly but not too tightly. Hold the needle with the slipknot and tail in RH. Holding working yarn tensioned with LH fingers, hook left thumb under working yarn from back to front.
Keep yarn tensioned around left thumb and insert the tip of the needle into front of loop on left thumb. Tail yarn is still held tensioned in RH at this point. Use RH to bring tail yarn up under needle, from right to left, take it between thumb and needle, over top of the needle, and hold tensioned to right.
Lift loop on left thumb over tip of needle, remove thumb and draw up working yarn. Two stitches on RH needle (slipknot counts as one stitch). Repeat steps 2-4 until number of stitches required have been cast on.
Make a crochet chain several stitches longer than the number of stitches you need. Fasten off the chain loosely. Insert the needle into the bump on the back of the crocheted chain. Knit once into each bump until you have the right number of stitches for your pattern.
When you are ready to unravel your provisional cast on, simply return to the crocheted chain, loosen the end and pull back the chain. As you do so, the live stitches will be exposed. Place each live stitch on your knitting needle as you unravel the chain.