Securing track-Newbie question

First off....Hello All!
I am a beginner and setting up an N gauge setup. I did some Model
railraoding when I was young but....
I fogot how I need to secure the track and I have done MANY searches
without an answer to my specific questions.
I have a base setup and it is covered with woodland scenics grass. I
have the layout of the track setup on it the way I would like but have
not secured anything.
What steps do I take to secure the track? Do I take up the temp layout
and the lay the roadbed? I have the woodland scenics trackbed.
How will I make the curves with the straight trackbed? What is the
best way to seccure the track to the roadbed?
And also, what are the steps I should take, for example, remove the
whole layout then install the trackbed,then secure the
track....something along those lines.
Thanks in advance for any help!!!!
ecavedude