First, I found a shield picture that I liked by simply googling "shield." It was gold and black. Jon used the same shield on his invitations.
It took a little photoshop magic to turn it into what I wanted: blue, green, red, and yellow to match the rest of his birthday decor.
this font to create the message: Happy Birthday Sir Nathan! You can obviously use any kind of font you like, and the site linked above has some great options.
I had a few other medieval choices, but it bothered me when they didn't have capital letters since I wanted to use all caps. So this is the one we chose. Celtic knots are a big thing with us (our wedding rings have Celtic knots on them) so we thought it was pretty appropriate.
The only problem was that the blue was too dark for the black outline and the green wasn't really great either, so I opted to change the black to white for those shields and leave the black on the red and the yellow ones (not pictured)
I was excited about how nicely the colors worked with each other and how great the looked all cut out, but when I laid out the entire thing, something was missing. It felt like they were bare or something - like there needed to be.. more.
So I had some fun with craft paper and decided a look like this would be best. And then I had to figure out which colors should go with which background. I used a pair of scrapbook scissors to get the "castle effect" on the outer edges. The shields are just shy of 5 x 7, so cutting out the backgrounds was a little challenging because I wanted to use one sheet for two.
I used gray yarn that I had in my yarn bin for a project I never did (surprise, surprise!) and it turned out to be the perfect use for it! ;)