I wish there were just some tips I could have shared and they would have made you an effective trainer.
Training is an art and science. If you have effective communication skills and presentation skills, you need to further gain knowledge and skills to master the craft. You may send me a test mail to get some e-books on training. I hope after readng them you shall be able to train more effectively. Call me if you need more guidance. All the best!
Just by reading the word "training" in your post, I would not like to give my comments. Trainers job is to develop critical thinking ability among the participants. Your training should not give them fodder in the form of knowledge but it should give them appetite. Your job is to develop ability in them to feed themselves.
As of now let me fulfil my inquisitiveness. What is your designation? Are you from training department? What subject or topic you would like to handle? Has this assignment been allotted to you by your seniors or is this your own initiative?
What is the education qualification of the participants? Is the presentation related to their primary or secondary duties?
Have you checked videos on presentation skills on the Youtube? Have you read any material on the employee training on the internet?
There are so many questions associated with your small post gentleman. The first lesson for you is to give sufficient introduction of your requirement. This is basic requirement of the communication. Training comes much later.