You can use this tutorial to make covers for seat belts or pram straps. It’s not recommended to add anything to car seats that doesn’t already come with it but saying that these would fit car seats also (great if use one for dolls or teddies).
This tutorial is for a seat belt cover but you do same process (twice) for pram straps.
For a seat belt you need 2 rectangles 9×6 inches and for prams you need 4 squares 7×7 inches. You can use cotton, fleece or plush/minky.
You’ll also need one layer of padding per strap. For this you can use iron on batting, normal batting, felt or fleece. Lastly you will need a strip of Velcro approx 2 cm smaller than height of strap.
Place the piece right sides together. Make sure the velcro is on opposite sides or the strap won’t fasten.
Starting about 0.5cm from the edge sew around all 4 sides leaving a small gap at the top. Trim corners. Turn out ensuring corners are pushed out and top stitch securing the gap.
You did it. Now use with pride. I also found this is great for bag handles so if have an uncomfortable strap add some extra padding and whack it on.