The easiest slipcover pattern ever! Make the chair too!
2 yards fabric per 2 chairs, 45" (I use decorator weight)
thread and notions
cutting board and rotary cutter
1 - 20" x 48 1/2" Fabric
2 - 45" x skirt length
Please read through the entire plan and all comments before beginning this project. It is also advisable to review the Getting Started Section. Take all necessary precautions to build safely and smartly. Work on a clean level surface, free of imperfections or debris. Always use straight boards. Check for square after each step. Always predrill holes before attaching with screws. Use glue with finish nails for a stronger hold. Wipe excess glue off bare wood for stained projects, as dried glue will not take stain. Be safe, have fun, and ask for help if you need it. Good luck!
UPDATE: The first, FIRST thing you have to do is make the chair.
The first thing is to cut your fabric. I made two chair slipcovers, and because I used directional striped fabric, I layed out the pieces as shown in the diagram. If your pieces do not have a direction, you could lay them out differently. Also, I made my skirts 12" long - you can make your skirts any length with 18" being floor length. From 45" wide fabric, you will need to cut two strips per chair.
Take the main seat/back piece and fold it over with right sides together so the fold overlaps 16 1/4". Pin and stitch with 1/4" inseams along edge.
At this point, I recommend fitting the slipcover over your chair to make sure the fit is right. If you are satisfied, remove and then clip in 1" at base of fold over as shown in diagram.
Then fit slipcover back on chair, still with wrong side facing outward. The corners will come to a point as shown in picture. Pin and draw a line over the excess fabric as shown in photograph. Remove and stitch over line. Clip off excess fabric leaving 1/4" for seam allowance.
This completes the seat/back! Turn so right sides are out and fit over chair. Now all we need is the skirt!
Now you can add the skirt by gathering or as I did with a single kick pleat. I thought the kick pleat was easier. If you choose to gather, simply gather along one edge of the entire skirt, pin and stitch in place and finish your back seam.
For the kick pleat, line up the center seam of the skirt with the center of the main seat/back piece. Pin. Then pin and stitch from center outward, turning front corner, stitching along side still at 1/4" seam, and then turning back corner. Stop after 2" (approximately) from back corner.
Do the opposite side, starting again at the front center and turning front and back corners and stopping approximately 2" after back corner.
Now we just got this back piece of the skirt to figure out. No biggie. What I did was sew the two skirt ends together first. Then I found the center of the back piece and matched up with center back seam of skirt and pinned. Then I pinned excess fabric into a kick pleat with right sides together. And then I just stitched it all up. Super easy.