Sure, LyX gives easy access. On top of that, using TeX
sometimes gives you more control and finer customization.
If you would like to have pure LyX style answers (click here, choose that, enter the menu, click, enter value, press ok, ...) then I recommend that you ask at the
LyX mailing list. This place here, the forum, is especially good in giving you LaTeX code which you could directly copy into your preamble (LyX menu: Document, Settings, preamble) and it works. Not much words and clicking around, which is often hard to describe.
Regarding page layout: I would use a class with best layout support. This could be memoir or scrbook. The latter would be my choice, which would mean for LyX, I choose "book (KOMA-Script)" as the class. Furthermore, I let this class calculate the layout, by adding the class option DIV=10 in the LyX dialog for class options. To get narrover margins, I use a value higher than 10. The layout is well calculated then, by page division. It's described in the link I gave above, there's a whole chapter about page design.
Stefan