Bias Binding Tutorial

This is a type of edge/hem finishing, this tutorial shows how to sew a bias binding. It can be used at the neck, hem, armholes etc or even to finish a seam where it is known as "Hong Kong" finish. Bias tapes can be brought ready-made or you can make your own. Today's sample is made using pre-made post. A bias binding that will finish 1/4" when bound will measure a total of 1" tape when unfolded (i.e 1/4"×4): in the same vein, a bias tape that will finish as 3/8" will measure 1.5" when unfolded.
The most common bias tape in Nigerian markets measures 1" when unfolded and will finish 1/4" when used for binding. This type is actually called "1/2 inch single fold bias tape" because it measures 1/2" till when unfolded.
It should be noted that an edge to be bound doesn’t require seam allowance, as sewing a binding merely wraps (or binds) around that particular edge and doesn’t take in any seam allowance.
You can sew a bias binding "in the round" or "in the flat". The SewExplicit forth coming pattern feature bias binding finish in the neckline, armhole/sleeve, and the sweep (hem). Sewing "in the round" means you are swing in a continuous circle, say for example, your armhole after the side seams and shoulder seam have been sewn. It is possible also to bias bind the armhole before both or one of the side seams and shoulder seams are joined together. That will be "in the flat". While sewing "in the flat" is easier than sewing "in the round", it creates bulk at the joints.
In the flat
for easier understanding, let us label the bias tape. On Opening up an 1/2 inch Single Fold bias tape. there are two fold lines separating the tape into three panels. Let us label outer narrow panel to the right as A; the centre panel as B and the left outer narrow panel as C. (these marks are made from the inside/wrong-side of the tape)
1. Measure along the edge to know the required length of bias tape to cut, add a bit extra (say 1" ) extra. 
2. Align the edge of the "A-panel" to the garment  edge you want to bind with the right-side of bias tape and wrong-side of garment facing each other; Start sewing exactly on the bias fold line

3. Continue aligning the bias tape edge to the garment edge as you sew, being careful not to overstretch the bias tape or the fabric edge you want to bind.
4. When you sew to the end, turn your garment to the right side, then flip over the bias binding thereby enclosing the raw edge. 
5. Fold the bias on the second fold line, ensuring that the edge of the C-panel is tucked in, out of sight. In doing this, ensure that half of "B-panel" is on the wrong-side of the garment and the other half on the right-side of the garment.
*Note: if none of the "B-panel" is seen on the wrong-side of garment but all of it is on the right-side, then you have not bias-bound. You have "bias-faced".

7. Top stitch on the B-panel from the right side of the garment close to the edge of  the tucked-in fold, ensuring that the stitch line we made in steps 2&3 is not showing.
8. Sew to the end. Viola!
Note: in the above steps, I started from the wrong side of garment and finished on the right side. it can be done vice versa, but I prefer this order.
the wrong-side stitching is not so neat uh? That is why I use the order above beside, I have used mismatched colour of bias tape and thread which makes it glaring. In real life, you will be matching thread, tape and (maybe) fabric colours.

Sewing in the round
1. Cut a length of bias tape that is 2 " longer than the edge circumference
The extra is needed has "handle" and will be trimmed off later
Pick a starting point. For example, in sewing a bias tape round a sleeveless armhole, I will pick the side seam junction as starting point, so the seam of the bias binding will coincide with that of the side seam
2. Align the edge of A-panel to the garment edge you want to bind (with right
-side of bias tape facing the wrong-side of garment). Working from the wrong-side of garment  ensure that the Bias tape is placed such that there is excess of about 1" beyond the starting point. But do not start sewing from the start point.

3. Start sewing on the fold line (about 1/4" sewing allowance) starting  about 1" away from the selected starting point. This will leave a length of about 2" of bias tape not sewn.

4. Continue sewing pretty much like "in the flat". Aligning the A-panel to the garment edge, sewing exactly on the fold line and being careful not to stretch the garment edge.
5.Pause sewing about 1" to the "start point".

6. Using the excess tape as handle, determine the required length of bias tape to close the binding on either sides (you can mark or notch the points where they meet).

7. When this has been determined, join the two sides of the bias binding together to form complete loop of bias tape. Open the seam flat and trim excess to about 3/8" Note: when joining the two ends, note that the c-panel is opened flat before joining.

8. Then you can now finish the stitching of the edge of the "A" fold to the bias edge to the garment edge.
9. Turn the garment to the correct side and follow steps 4-7 of "in the flat" example. That is you flip the bias binding to the right side of garment; you tuck in the "C-panel", you top-stitch on the "B-panel" close to the tucked in edge, careful not to reveal the line of stitching previously sewn. Viola!
Remember, Practice makes perfect. If you don’t get the first time, keep trying.
Other tutorials from the web  I really like this one hereHere and Here,