Asalam Alaikum,
Your shalwar cloth should be at least 32" by 96". If it is wider that is good, but the minimum is 32".
Step 1-
Fold the cloth in half length wise, then width wise. Arrange so that the selvages are facing towards you with the with the four corners on your left side.
Step 2-On the fold side measure down your desired length(to find your length measure from your waist to just below the bone on your ankle) plus three inches, and mark. Measure on the selvage side also, then mark and cut straight across.
Step 3-On the side that you just cut measure from the fold side down seven inches and mark. This is the bottom of the shalwar, it must be wide enough to put your foot through with a bit of extra space. Measure around the ball of your foot and if you think you need the leg a bit wider you can add a couple inches, but seven(fourteen total) works for most.
Step 4-On the selvage side mark at the half way point.
Step 5-Draw a diagonal line connecting the two points, and cut along the line.
Step 6-With the right sides facing each other, match up the selvages of the four triangles to the four selvages of the main shalwar pieces, and sew a half inch seam.
This is the approximate position of all the pieces.
Step 7-On the triangular piece that you just attached to the main leg, you will cut off the outer point because this is for the crotch seam. Measure straight down from the top, you want the edge to be 17 inches, draw a line and cut the excess. You can sort of see in this picture where my chalk mark is, it should be several inches out from the seam that you sewed in the last step. You should do this for all four sides.
Step 8-Now you will sew the crotch seams. Place the two pieces together with right sides facing. First sew one seam from the top straight down one side(green line in the diagram). On the second side(the seam should be one inch wide) start one and a half inches down from the top and sew straight down.
Step 9- On the seam that you just sewed, press the edges away from the seam. Fold the raw edges under half an inch, and sew as in the picture below.
Step 10-Now sew the space for the drawstring. Starting at the opening you made in step 9, fold the top down half an inch, and then fold again one more inch and sew along the bottom of the fold. Sew all the way around the top, until you come back to the opening, and sew over one inch of the first stitches to secure the opening.
Step 11-For the bottom of the feet, you will need a medium weight interfacing, you could use a fusible if you want, but we don't. Cut two stripes that are one inch by 18 inches.
Step 12-On the wrong side of the cloth place one piece of interfacing, and fold over one half inch of the cloth and sew one line to secure the interfacing.
Step13-Fold the interfacing and cloth up on the wrong side another inch, and sew six to eight straight lines along the area where the interfacing is.
You can kind of see the lines in this photo-
When you have finished cut the extra interfacing even with the cloth.
Step 14- Now you will sew the inside leg seams.
With the wrong sides facing measure on both of the foot openings out from the fold seven inches and mark.
At the crotch seam measure up half and inch and mark
Mark a straight line to connect the mark at the crotch seam and each of the marks on the foot. Sew from one of the foot openings straight along the line to the crotch seam, turn and sew four inches down on the second side. Turn and sew back along the line to 4 inches past the crotch seam over the first line of stitching and then turn one last time, sew up to the crotch and completely down the second side to the bottom of the foot. This back and forth may seem a bit much, but it is always good to make this seam a bit strong just in case.
And that is it, the finished simple shalwar should look something like this(ignore the white lines, my cloth had a misprint that I didn't notice when I bought it).
If anyone has any suggestions to improve this tutorial or if you found it confusing make a comment and let me know.