Full term training means - you have to be a trainer. In order to qualify yourself as a trainer, you should know the following personal technical: 01. Communication ability - fluency in language, knowing the subject well, audience control, ability to clarify the doubts in the subject at any point of time, control over personal negative traits, tolerance etc.
No books can offer you the above training. Whatever you are going to hear from others will only be a information.
Get into the field. If you want to swim - do not think about swimming - just fall into the water and learn swimming
Capture all opportunities made available to you to talk in front of an audience whether it is a small group or large group. Larger the group, you can master your skills still better. A driver becomes a better driver only when he continuously drive the vehicle under all conditions. Similarly, train yourself to conduct the training at any environments.
During my first training exercise as a trainer, I struggled harder not in concentrating my subjects, but in building my confidence level. Today after more than 4000 training hours, I am very comfortable and I bother about the subject only and not the audience

Wish you all the best