craftgrrl | Help me out? crochet (Reply)

Today in a burst of impulse I bought 6 balls of “wool-ease thick and quick lion brand yarn” to make my bf an afghan, not yet even knowing how to crochet. I also bought a beginners book, and I have succeeded to figure out the simple patterns so much so that I can make a scarf sort of thing now.

Now my problem is, how do I put together a blanket with six 6 oz/170 grams & 108 yards/ 98 meters of super chunky weight yarn?

I am such a beginner at this, I need to know if there is even a way to put together pieces of crochet without it being obvious to the eye?

Should I just start working and make uneven rectangles and hope to be able to put it all together at the end? Im very confused as to the ratios, etc.

Or maybe I should make even sized squares so they’ll at least have some sort of consistency?

ANY tips would be welcome.
Thank you guys so much