1_ The beginning concept was an image made in Illustrator. I used it to have an idea of the whole shape before start modelling.

2_The reference was used also as background image in 3d Max. On the top view go under View Panel and select Viewport Background or press "Alt+B" for the shortcut. Assign the path of the image to load. Now select "Match Bitmap" in the "Aspect Ratio Panel". Select the voice "Lock Zoom/Pan". Now you are able to zoom and unzoom the image in the back within your geometry object.

3_ Go on the create Panel and select the shapes menu. On the Splines menu select "Circle". Now put the mouse on the centre of the circolar shape of the reference and drag a circle. If you have a problem to see your spline there is a little tip to use: because of their thin dimension is raccomended to activate in the modify panel of the shapes, under the "rendering panel", the voice "renderable mesh". Now the splines results more visible. It is very useful in case you are creating a complex spline and you have a white background. Remember to deactivate in case you didn't use it at the end of your work.

4_Now select the shapes and go under the modifier list. Select bevel. You are now able to execute a bevel operation from you spline. In the bottom part there are 3 levels of bevel. Now pass in a Perspective view to see the effects of bevel modifier. You have three levels of bevel so you are able to create a symmetry geometry. Put this values:
Level 1: Height: 0,5
Ouline: 0,5
Level 2: Height: 1
Ouline: 0,0
Level 3:Height: 0,5
Ouline: - 0,5

5_The useful aspect of this tecnique is that you have full control of the shape in every moment. You can change the aspect of the geometry changing the vertex of the spline in the sub-object mode.

Now we make a little complex object. For example we start creating the shape highlighted in blue in below.

6_This shape is not regular as the circle so we have to use the splines in all their capacity. On the Create pannel select "Splines" and then "Line". Before starting to create the line, in the "Creation Method" choose Smooth for the "Initial Type" and for "Drag Type". This allow you to control the tangency for every point of your spline. Create the whole shape and refine the spline adjusting the tangents. Now that you have the correct profile apply the "Bevel" modifier. The values remains the same of the previous operations, so the result will be similar as the circle done before. There is another way to do this. If you want the same values of the circle, for example, you can select from the circle's operator stack the beve modifier and drag it onto the new spline. Now the new spline has the same bevel modifier of the circle.

7_ Now create spline for all the elements and apply the bevel. The final result should be similar as the figure below.