This is that tabard.
I apologize for the lack of visual documentation. I did not take any pictures as I was doing it, only decided to make an instructable about it after I had finished it. If I make another one, Ill post pictures from that.
1st is the front, second is the backside. On the front, you can barely tell that the collar is a little lower on the front, and the seams on the edges come in right next to the black strips.
By the way, this tabard is entered in the Game.Life Contest! If you like it enough, please vote!
Step 1: Materials
The day I got the fabric I went to JoAnns. They had a sale on colored canvas that day, (and the fabric was 65" wide to begin with) so I was able to get enough fabric to make a couple tabards for around $10-15.
As for the amounts, you just need enough canvas to be cut into a 2x6.5ft rectangle (for the main body. 2x3.25ft on each side), and enough to make a 3/4" wide strip 4ft long. If you want to make a design in the middle (I have not yet done that), get enough for that too.
Step 2: Starting to Make It
Start with a 2x6.5ft rectangle of whatever color you want. Fold it in half, and crease it really well, so you have a separation between the front and back. This crease will go right on top of the shoulders. Now you will start cutting.
You will be marking on the fabric, so use something that can wash off, such as chalk.
Lets start on the front. For the arm holes, mark a rectangle 2inches in (on the crease) and 11 inches down. Freehand a slightly curved line inside the rectangle (see diagram). This will be the exact same for the other arm, and on the back.
For the lower part on the front, mark a rectangle from the corner 6 inches in and 16 inches up. Make a curve inside it as shown (I flared the very bottom inch a slight little bit). For the back, it will be just the same, but instead of 6 inches in, it will go only 3 inches in. Cut all of these marked parts out.
Now for the neck holes. The neck holes start 2 inches in from the edge of the cut shoulder. On the front, it goes 6 inches down, and 3 inches down on the back. (once again, refer to the diagram for clarification)
One thing to remember: make sure the neck hole is centered just right. Otherwise, it will fit oddly. Also remember that the curves are inside the rectangles that you marked.
Now you have your basic tabard.
Step 3: Sewing It Up
This is a fairly easy part if you have basic sewing skills with a sewing machine. The stitch I used for this entire project is a jig-jag stitch, and the thread was a black upholstery thread. Its a lot more heavy-duty than regular thread, just right for canvas.
Fold every edge (including the neck hole) 1/4 inch inwards, and pin it in place (you will be sewing a continuous edge, so pin all edges at the same time). For this part, lay out the tabard flat again. It makes it much easier.
Sew it all around, and you are done with this part!
Step 4: Adding Trim
Start by cutting 1.5 inch strips of black and sewing them together to get a 4 or 5ft long black strip. Fold both edges 1/4 inch in and iron the crease so that it stays folded, to give you nice clean lines. This should leave you with a 1-inch wide strip.
Lightly mark the line that the strip will follow around the tabard (the strip will be on the side of the fabric that the folded part is not on). On mine, as you notice, the strip is as close to the edge as possible on the shoulders and bottom part ("tails") on both sides. In between those parts, I just freehanded a slightly curvy line that connects both areas.
Pin the outside edge of the strip along this line, and sew it down (you need to sew both edges of the strip to make it stay in place) using the same stitch as before.
Step 5: Done!
You can complete the look if you wish (and if you have the money) by buying the maile shirt, helm and gauntlets from ThinkGeek, but thats a little bit pricey. However, it would look pretty awesome.
Have fun! Message me if you have any questions!
(I was thinking of saying something like "May Elune be with you/For the Horde" at this point, but that might be a little too cheesy :P)