Mozilla Developer Network (MDN) is pretty thorough,
but may be a bit technical. Read through it and see
if you can find the section that'll help you. If
it's not helpful then keep searching online!
Interesting (and optional) background reading on
pseudocode
from Wikipedia. The most useful thing to learn from
this article is that there is no 'one true' pseudocode - you
can pretty much wing it and it's all good :)