How to create topographical map?

[officiallyme]

Hi all,

 

Unfortunately I am completely new to AutoCAD. First time I am using it, actually.

So far I can't really make heads nor tails of it

 

I'm trying to create a topographical map of a lake, i.e. I want to draw the coast's outline and then ad the lake's depths.

 

The lake looks basically like the attached image (green are trees, yellow is beach, blue is lake.

I would like to create that kind of map with AutoCAD and add the lakes depths.

 

Here is a map I found in google where you can see a very "basic" 2D version of what i am trying to do

 

I'm not sure where or how to start. How to draw the basic layout just like I did in the attached jpg (simply drawed it in photoshop).

 

Hope you guys can help me out

[ReMark]

One possible option. You could try bringing the image into AutoCAD and literally tracing around it.