Hey buddy, Its important to know Best CAD/ CAM software. As their are many free or paid software available in market. So i think to list some free CAD/ CAM software:-
Free CAD software
NanoCAD
Wings 3D
DraftSig
Free CAM software
FreeMILL
G-Simple
PyCAM
Those who want to get in depth details about Here is one nice article on them:-
You can also look for some paid software also if you want more features