There are two looks you can get from crocheting in the round - an octagon/heptagon whatever gon but a gon nonetheless - or a circle.
When you are working in rounds and you want your piece to look more squared off - or have "corners" I guess you can say (I will try and add pics later if I can crochet up a few samples for you) you work your increases in the same spot
round 1 - ch2, 6 sc in second chain
round - 2 sc, sc around
round 3 - 2 sc, sc in next two around
round 4 - 2 sc, sc in next three around...
and you keep doing that increase around and around and around.
okay, to make your circle not so pointy and whatevergon shaped...
all you need to do is do your increases in a different spot each time - when you look at the above example - you will see that you are making kind of sections... do your increase in each section (you know your section is the increase and the next few scs.. ) so just stagger where you do your increase so it isn't on top of the increase before that one.
like in round 3, you would sc, 2sc, sc in next two...around and when you get to the end of your round, you would finish up the scs that would have been in that first section.
round 4, you could sc in 2, then 2sc then sc in the next 3... blah blah blah. I think you probably get that.
It kind of makes sense.
Here is a great Japanese site that shows the two differences so you can see what I am talking about..http://www5a.biglobe.ne.jp/~mite/gurumineko/4/kagibari16.html
sorry about the japanese but it has pics that you can see what I am talking about how the two ways make a slightly different shape..
now.. laying flat... if your piece starts to curve up and get bowl shaped then you are either doing too many increases, not enough increases or your hook is either too big or too small... tricky thing.
I think the most common round one for working in the round is starting with 6 sc... so I would give that a go and see how it goes.