First, do not try to make a “confection” training to ease your job, instead try to go on with a “boutique” training. Your users will have different levels of knowledge and you will need to arrange your training accordingly. You cannot deliver the same Microsoft Excel training to the employees in the financial department and the employees in the human resources department. Employees in the financial department will be using a lot of Excel in their daily tasks and most probably mastered it because it is one of their core applications in their daily jobs. On the other hand the HR employees will go so far about goal seeking or working with multiple workbooks, because their core HR application is different. By knowing your audience, you will be able to keep the sessions running smoothly, rather than jumping back and forth with the concepts that some people know and some do not.
To warm up people, most trainers fall into the company-talk trap to warm up the people. Company-talk is about speaking too much, in some cases giving too much personal opinions about the company. This can be about the company the trainer is an employee of or a totally different company, such as Microsoft in my case. People are in the same room with you because they want to learn certain skills to keep themselves productive. Instead of speaking about the company, I advise the trainers to talk about how people can benefit: if it is an application training, show them how the application will help them in their day to day tasks, if it is a security training, tell them about the recent user data breaches that big companies such as Adobe, LinkedIn, Target, Snapchat faced.
Some people in the training room will be thinking that they know everything and there is nothing for them to learn. As trainers, we cannot deny the fact that some users are more knowledgeable than the others. But we have to tell them explicitly that they are also vulnerable too. To draw their attention, I advise to give real life examples of creative attacks which target the human element rather than systems. This can be dropping USB drives in the company, phishing scams and the like. If you can get company approval and perform an in-house security test and include in your training, this will be even better.
It is also very important to choose the right trainer for the in-house training. It is no secret that IT people are not as good as sales or HR people in communication. In IT training, you need to have a trainer that is a good communicator, has a deep technical knowledge and can convey this information. When conveying this information, he should not forget that the people in the room are end users, in an engaging manner. If you are delivering security training and you speak about proxy servers, IP addresses, ports and firewalls, then be sure that you lost the classroom. I have seen a Microsoft Outlook trainer who was talking about e-mail domains, relay addresses and MX records when the audience did not know how to use the calendar to invite people to meetings.
When preparing your IT staff for the in-house training, select a few people who are willing to give training and monitor their performance as trainers. You may find that some of them become better than the out-of-company trainers. You may also ask sales and HR people, who are used to prepare presentation materials and who are used to speak in front of people, to assist your IT staff in preparing for the training.