1. you need to master the basic knowledge of electrical
2. online tutorial of next PLC can start Mitsubishi plc, easy to use, most information PLC software download
3. online not only programming software, and programming manuals, software manual
4. look routine, learn other people‘s programming ideas
So you probably already understand the program, and the rest is practice. Understand the basic process flow, then programming is not difficult.
PLC ONE 