This has become my favorite tradition in which we celebrate "special days" at our house...
It's just a simple chair cover that I slip on a family member's chair (yes, we have assigned seating at out kitchen table!) for the day when it's a special day for them. It's mostly pulled out for birthdays but I love that's it's generic enough to use for any other special days like anniversaries, school celebrations, milestones, etc.
I'm no seamstress and this was pretty easy to put together. For the "special day" lettering, I just found a font I liked, printed it off using a size that would work, pinned the paper to the fabric, and started cutting. I don't have any fancy equipment, or this really could have been a cinch.
For the "My" I took blue grosgrain ribbon and "gathered it so it would bunch up. Then I pinned it as best I could to the cover and sewed a strait stitch through the middle of it. It was a little tricky and it didn't end up perfect but close enough in my opinion.
I do like that the sides tie because that way it will fit over any sized chair, big or small.