andermra..I've posted a link to a site with patterns for toddler and infant car seat covers. The pattern is 10 dollars....BUT...the lady will BARTER for things she needs instead of money. On the page, you will see "free patterns" listed on the left side of the page, part way down. Click on this, then scroll down that page to find what she will barter for.
The pattern description says it will work on different kinds of car seats...
Hope this has helped.

Here is a link that might be useful: Car seat cover

Kwik Sew sells a pattern, also, for a cover for a car seat and a cover for a stroller.

CMC

Here is a link that might be useful: Kwik Sew 2470

Go to your local thrift shops,especially DAV if you have that where you are.You can get patterns there for 35 cents.I got about 6 today for my GGD.
Kathi

I did this several times back in my rice and beans days. Why pay for a pattern that probably wasn't made for your car seat? Just take off the old one, trace around it, add seam allowances and sew. If the old one is in good shape and you just want to change the fabric, just wash it real good and make a slipcover for it.