Here is a tutorial and it is very picture heavy but you know what they say a picture is worth a thousand words.
This is how I put on a neckband on a knit garment.
Start off by measuring the neckline of your pattern. Turn the tape measure on the side to get an accurate measurement.
Take this measurement and subtract the seam allowance, in this case the seam allowance is 5/8". Kwik Sew patterns are probably 1/4", just check your pattern instruction sheet. Then I always write this measurement down on the pattern front, it is your pattern, mark it up.
Now measure the back pattern piece the same way.
Subtract the seam allowance and mulitply by 2. Write it all down.
Now back to the front pattern piece. Write down the front measurement and the back measurement and add them together. This number is your finished neckline measurement.
Now just for fun I measure the neckline binding to see what the pattern piece has allowed. The pattern I am making isn't just for knits, it is for woven fabric too. So the two measurements aren't that different. A pattern designed only for knits might vary more.
Now subtract the seam allowance, in this case there is 5/8" on each side of the neckline binding. I multiplied the 5/8" by 2 for the 1-1/4" total seam allowance.
This pattern I was using had a 1:1 ratio for the neckline and the neckband measurements. See above for the front and back pattern measurements.
Now here is the tricky part and I don't have a set way I figure the neckband I want to cut. I change it according to the stretch of my knit. Lay the knit out next to a ruler with the stretch going the length of the numbers.
I pulled from the 4" mark and my knit stretched to the 6" mark. Not too much stretch in this case.
I meaure the neckband pattern piece for the width and then cut my neckband piece with the rotary cutter. I get a much straighter piece, which results in a better looking finished neckband. This number isn't set in stone, you can adjust the length to whatever you want. My pattern called for 1-3/8" width, I cut this width the first time and decided it was just too narrow, so I cut another piece 1-3/4".
Now back to what length I am going to cut my neckband. I decided to use a 20" piece including seam allowances (18-3/4" is the finished length). I want the garment to pull toward my body. Usually with a pattern piece, the neckband is too long and the garment doesn't hug the body. I always cut my neckband shorter than the pattern piece.
Attaching the neckband to the garment
Meet the shoulder seams
Put a pin in the center front and center back
Now match up the center front and center back pins. Then mark the fold with pins. These pins will be in the front of the garment, not at the actual shoulder seams. In the case of this pattern the front pattern measured 11-1/4" and the back 10-1/4", not much difference. So my pins will be 1/2" from the shoulder seams on the front piece.
Note: Most knit patterns have a lower front neckline so your pins at the side will be more toward the front.
Here are all 4 pins
Sew the neckband into a circle and press it in half
Mark center front and the seam will be center back. Then match the center front and center back and place pins. The neckband will have 4 pins and essentially be sectioned into quarters, just like the neckline.
I start by matching the center back of the garment with the center back of the neckband and pin. I pin the neckband on top of the garment.
Once matched, remove the pin from the garment and use the pin from the neckband to pin the two pieces together. Continue around the neckline and attach all four pins. Here is a good time to check out much your neckband will have to stretch, if it pulls too much and distorts out of shape, the neckband might be cut too short. Then in the same sense, if the neckband really doesn't stretch much, then it is too long.
Now it is time to serge. I adjust my differential feed on my serger to help ease in the fabric of the garment.
Start at the center back, stitch for just a bit 1/2" or so, locking the neckband to the garment. I then stretch the neckband to the next pin and sew. Continue this for the entire neckline.
Now press this seam flat
Lay flat on ironing board, wrong side up
Press this seam, then turn garment over and press on the right side, too.
Now take it to your coverstitch machine or your sewing machine for topstitching around the neckline. I have to remind myself to watch the presser foot and not the needles. If I remember this, my coverstitching is much straighter and neater.
Then one final press
The finished neckling
A little closer view
I hope this makes sense and isn't too confusing.
It is a bit of trial and error to figure out some knits. It really depends on the amount of stretch.
I have to thank Anne of Needle Nook for helping me with my knit sewing. She is the best