Do make layout sketches to illustrate your design plan.
Do make daily (hourly?) backup copies of your work.
Don't be afraid to try things. You can always erase. You can also make copies of your part file to experiment with.
Datums are free. Aside from an extra line on your feature tree, they don't cost anything in regeneration time.
Sometimes temporary surface or solids are helpful to define geometry.
Delete Bodies is a good way to clean up your model at the end.
I can definitely recommend the complex shape modeling book from Matt Lombard as well. Best SolidWorks surfacing book on the market in my opinion. Surfacing is a complex and large topic and there's a lot of ways to accomplish what you are trying to achieve. For me with regards to surface modeling I prefer to build to theoretical edges as much as possible rather than overbuilding and trimming back, but I use both depending on the situation. here's a few do's from my perspective.
-Use style splines with as few control points as possible, this will result in cleaner surfaces.
-Build Large 4-sided surfaces to theoretical edges that define most of the shape. (Pirmary Surfaces)
-Build blend surfaces next to round off the sharp edges. (Secondary Surfaces)
-Finalize shape with final blend patches. These are often the most difficult to achieve (Tertiary Surfaces)
-Following on theoretical edges, try to avoid building primary surfaces from trimmed edges. Trimmed edges have increased complexity and consequently surfaces build from trimmed edges have increased complexity in surface structure and increases the chances of surfaces not being smooth.
Another good do is to think about the surface structure before you start building. Sketching out surface patches before you start building can be quite helpful. Things to avoid when surfacing. Surface patches with singularities (where the control points converge to a point). Sliver surfaces. It is very difficult to maintain continuity if your reference surface is really small. Sliver surfaces can also cause problems when you try to thicken the surfaces into a solid. Try to keep surface patches as "square" as possible. All Nurbs patches are square and If the shape is too distorted it can be very difficult to keep the surfaces smooth.
This list could be a lot longer than this, but that is why you should get Matt's book
why such a big difference in price of printed copy and kindle copy? surely it doesn't cost this much to print the book:)
My only insight ..
Don't try to model the surface to the exact 'dimensions' you want. Quite often, you want to extend the surfaces past each other, over flow them, etc... and the let the trim/intersect tools take care of getting rid of the excess AND kitting them together. If you don't, that's when you get those slight but horrible wrinkles/defects that drive you crazy!
It's the one 'mindset' solid modelers have a hard time getting out of when learning how to surface model
Just my humble opinion .. It's something I emphasize h during every surfacing class I teach.