Tricycle seat cover!

D got gifted a wonderful Radio Flier Trike from our neighbors down the block. He LOVES it. he rides all over the place, as much and as fast as he can (he usually pretends to be a train of some sort, doing really useful work). He rides so much, in fact, that his butt is all bruised from the hard seat.

Ergo: mama has to make a cushion to protect his "widdle buddum"
just in case anyone else needs to do this, here's a step-by-step of how I made it.
Materials needed:
trike seat (remove it from the trike with pliers and elbow grease while batting away pesky toddler who's upset that you're messing with his trike)
foam (i bought 1/4 yard of 2"thick foam from joanns (ONLY buy it on sale, or it's ridiculously expensive. it seems to go on 1/2off at least one weekend a month, so wait for the sale!)
Leftover batting (i had some junky poly batting left from something old... )
1/4 yard of scrap fabric
scissors, needle and thread.

trace the seat on the foam with a sharpie

here's the shape of his seat.

the people at joanns told me to use a serrated knife to cut the foam. i don't think i have the worlds dullest bread knife, but all it did was make the sides look like this. so i turned to my kitchen shears

voila! a seat cushion shape!
cover it with batting (to round out the edges and ... actually, not sure why i did it, but i know you do this when upholstering things, so i figured i should do it for this....) i tacked the batting down with some quick and dirty stitches
these were the two semi-vintage red prints i had on hand, so i let D choose which he wanted. he chose zigzag (it looks like rows and rows of primary colored rickrack). (so glad he chose that one, i have jumper plans for the polkadot, but i have learned that i MUST give my boy a choice)
i laid the seat (with its foam and batting) on my fabric, and roughly cut the shape of the trike seat. (i took a rectangle and cut 2 corners off, so it was a very oddly shaped hexagon)
i used a lot of pulling and pinning, and threaded my needle with super strong thread, doubled, and sewed the fabric taut around the underside of the seat. i didn't bother covering the underside, cause it's not gonna rain upside down, nor will D be riding through lots of puddles in drought-ridden (ha, pun) SoCal.
TADA!!!!
D won't stop riding to let me take a cute picture, but at least it's getting used!