Ha! I went to school to be a draftsman. When I got out, CAD was a new thing and they were laying off draftsmen all over industry. Couldn't get a job in that field for trying. So, got a job as an apprentice machinist instead. CAD is interesting because some things that were so simple to do with paper and pencil take hours to master in CAD, but on the other hand, some things that took a lot of figuring on a drafting table happen almost instantly when doing it on a computer.
But, anyone that wants to try it can easily download any number of free 3d CAD programs and watch some youtube lessons to get the hang of it. If it is something you decide you want to do, then deciding on your 3d program you want to stick with becomes a little more complicated. Obviously the bigger your budget the more options you have, but professional programs bring with them a lot of functions you will never really need or use. I like using Rhino 3d because it is command driven, ala, Autocad variations, but you certainly don't even need that much power really. Best thing to do is download and install anything that is free and try to use each one to draw the same "something basic" in each one to find out which feels more comfortable to you and go from there.