Crocheting a ball

[zombiesatyour6]

Ive looked at 2 or 3 patterns for crocheting a ball and they always come out egg shaped...Im trying to crochet a planet and cant for the life of me get a perfectly round ball :(

any suggestions? I dont know how to do the magic circle thing so I just ch 2 and sc in the 2nd ch from the hook.

thanks