I will explain why I made this ball and share exactly how I did it.  Even if you had never heard of a Luxo ball until just now, this tutorial may be helpful to you.  It is helpful for anyone seeking information about how to crochet a small sphere. It is helpful to anyone who wants to know how to change yarn colors partway through a project.  This post also contains information about embroidering onto a crocheted piece.

This ball was originally featured in the first toy story animated movie. Since then it has become a sort of symbol of Pixar.  The animators place this ball somewhere in every Pixar movie. Superfans will watch the movie seeking a glimpse of the ball.  The placement of this in each movie is called an easter egg.  I guess since people hunt for them while watching a film.

My son has just learned of this and has become extremely excited about the "easter egg hunt" in each movie.

My son also makes his own movies.  He makes stop motion videos with his toys as the actors.  I made this ball thinking that he may enjoy hiding it in the background of his movies, just like the professional animators do.

This really is a quick project that uses only a tiny amount of yarn.  I made mine as tiny as I could so that it could go in the background of the toy videos my son makes.

You can make these in any size that you want.  You would simply crochet more rounds, until you reach the desired size.

The first ball I started to make was too large for my purposes, but it would have been the perfect size to be a hacky sack or a beanbag.

This ball is made in two pieces that are joined as the last step of the project.  I tried to make this in one piece first, but the ball came out so much rounder and the star was so much easier to make when I made the two halves separately

Start:

Magic circle with your yellow yarn 

single crochet ^ times into magic circle

round two single crochet twice into each stitch of the previous row

round three- alternate crocheting one single crochet into a stich, two single crochets into next stitch.  Repeat 1sc and 2sctogether for the round

round four -  like the last round, but this time put two stitches in between the increase stitches.   it will go  1sc  1sc  2sctogether repeated for the rest of the round

 cut off your yellow yarn leaving a few inches of a tail and leave it for now.

Time to make the other side.  Start over again at the beggining and follow the  steps again untilyou have two yellow crocheted partial balls  with four rows each.
 
ONLY ONE YELLOW SIDE WILL NEED BLUE ROWS NOW.  THE OTHER HALF WILL ATTACH LATER
pick up your blue yarn and begin crocheting with that.  You do not need to make a knot.  We will tuck all of the tails inside the ball at the end

round five-  single crochet into each stitch

round six- 1 sc into each stitch

round seven- same

round eight- same

Youare done crocheting.  
You may cut off your blue yarn leave yourself a couple of feet to attach the two sides later

You should now have one yellow circle with four rounds and another piece that is yellow for four rounds and then has five rows of blue

With your yarn need;e , stitch the shapeof a star on each half . 

when you have your stars done, it is time to stff the ball.

I stuffed it about halfway and then I threaded the long tail of blue yarn through my yarn needle and started stitching my two sides together,  

I pulled my needle into the places between crochet stitches on first one side and then the other until I was halfway around my sphere

Stuff your sphere more , I used my crochet hook to really pack it with stuffing.

stitch around connecting the two sides even more.

Add any final stuffing and then finish connecting the two halves.

pull all your ends to the inside of the ball 

You are finished