Crocheting a cube

Dear forum, I’m relatively new to crocheting.
Now I’d like to make a cube that will later be used as an amigurumi, just larger than in the pattern
The square should be about 68 stitches in size. (so 17 stitches per side), if not larger.

I started with a circle and then kept increasing in the corners. I crocheted into both the front and back loops.

Question:
How can I now crochet upward?
and do I need to use only the front loop or only the back loop?

Before crocheting one sc into each stitch, the pattern had some decreases, but since I have a different number of stitches, unfortunately I can’t rely on the numbers.
I’m also using very thick yarn (crocheting with 7.00 mm) — could that perhaps matter?


Original pattern
https://www.craftybunnybun.com/cube-puppy-dog-amigurumi-pattern

Kind regards, Manuela ♡

Good morning, I can only guess.

Once you’ve reached your desired size by increasing in the corners, you’ll need to continue crocheting in rounds without increasing. That way, you’ll reach the height you want.

Then, close the bottom by decreasing in the corners again.

For the height, I would insert the hook into both loops. You could try inserting the hook only into the back loop in the first round without increases. But that’s a matter of personal preference—I’d give it a try.

Hope this helps. 

Thank you so much for your reply—I’ll give it a try.