I also use Sketchup - no longer Google, they sold it to Trimble but a very robust free version is still available called Sketchup Make.
If you go with Sketchup, there are tons of tutorials online. Use them and it will shorten your learning curve.
First, learn how to create groups, then learn to use levels.
It's too easy to merge lines from one item into another which creates difficulties. For example, if you draw a wall with an opening for a door and then draw the door without first creating a group of all of the lines that it took to draw the wall, your wall and door will end up merged and it will be harder to move the door later or copy it for use in another location. The software will think the door and wall are all one item. Once you create a group, you can also lock the group to prevent accidental changes.
Learning to use levels allows you to turn off things you don't want to see. For example, I created a site plan for my house and workshop and put various things like electric lines, gas lines, plumbing, driveways, fences, notes, etc all on their own levels. That way I can choose what I want to see.
Another thing to do when starting is to get the actual GPS coordinates for any structure you are going to draw. Sketchup has a cool feature that will show the correct orientation of the sun and shadows based on longitude and latitude. Starting your drawing as close as possible to the correct coordinates makes this feature more accurate. I think you can get GPS coordinates from Google Maps.
All in all, you have to be disciplined in your drawing efforts with any CAD software to make it easier to make changes down the road.
Good luck,
DC
