
I am also going to use felt blocks, but I am going to sew it more invisibly and use better colors.
In fact, I am going to use old sweaters!
I found my first one the other day, in a bag of clothes on the sidewalk. It was a men's medium, but I threw it in the washer with hot water then in the dryer; now I doubt if a five year old could get his arm into it:

See, it turns into felt when you do that. You can cut it now, without it unraveling:

Cool, huh?
So if you have any old sweaters that are mostly wool or cashmere, please send them my way! Seriously!