Let's start from the top.
Why, you ask? Because it's best to start on a high.
Get into it now.
Why, you ask? Because it's the smart idea to live by.
Come out now and breathe the fresh air.
Why, you ask? Because it's not right to intrude.
Move under it just a little.
Why, you ask? Because it would be rather rude.
Go through and get stuck now.
Why, you ask? Because it's rather rough here.
Come out altogether and go to the sides.
Why, you ask? Because you need more than one to conquer.
Move to the ends.
Why, you ask? Because it's good to have something close.
Back up and down the middle till it splits.
Why, you ask? Because those are the ones that appeal most.
Drop down to the bottom and stay there now.
Why, you ask? Because it's best to end with a game or two.
Too many questions here, that I know.
But perhaps no one knows the answers better than you.
What am I talking about?
All the clues are well hidden in the riddle. The best answer will explain every line perfectly.