How to start a career in SAP TM

Hi All,

I am looking for your advice on learning SAP TM. I do have experience on Logistics more than 5 years as I was working in 3PL company in Dot net platform. I want to get into SAP TM (functional consultant). I would like to know what are the things I should know (SAP ECC, SAP LE,...) before SAP TM.  Could any one please advice me where to start?

Thanks,

SJ