ABC Blanket

I am just getting started on an ABC blanket. I started last week and I have letters B, C, D, and M complete. Currently I am about half way finished with the letter E. No, I am not doing them in order, but there is order to my madness. When I started out I only bought one ball of blue and one ball of red, and only had a few letter patterns so I started there. Of course I had to chart out letters and colors first. I will be using blue, red, and yellow for the letters and numbers 1-4. I can get about 3 1/2 letters off of one ball of yarn, so I am looking at 3 yellow, 3 blue, and 3 red. The patterns for the letters are from Ravelry by Rhonda K. White. I am makings sure each letter has 36 stitches left to right and 57 rows up and down so they fit nicely together when I am done. I need to go on and find the number patterns. I have no idea which method I will use to connect this all together yet.
Yarn: Cascade yarns 220 superwash sport color numbers 813(blue), 809 (red), and 820 (yellow).
I am using a size 5 needle.
My Chart:

Red 1	Yellow A	Blue B done	Red C done	Yellow 2
Blue D done	Red E	Yellow F	Blue G	Red H
Yellow I	Blue J	Red K	Yellow L	Blue M done
Red N	Yellow O	Blue P	Red Q	Yellow R
Blue S	Red T	Yellow U	Blue V	Red W
Yellow 3	Blue X	Red Y	Yellow Z	Blue 4

I love that the letters are raised which will be great for learning letters for little ones! That is all for now.