That's why I'm often using checklists, just to make sure that I didn't forget anything important and sometimes bounce on some concept that could fit in and enhance the level.
Reading the following posts, you'll probably think "oh yeah...I already know this, it's obvious", and you'll also probably think " yeah...sure...but this isn't mandatory" and you'll be right :)
The following posts are not supposed to be THE rules of LD.
They are just key learnings and references to be used to avoid mistakes and boost design creativity.
Have fun!