One thing that helps you hold people's attention, gain rapport, communicate beyond the words and be memorable is PASSION. This is one element that you need to engage with and actively consider in how you present, what you choose to show and the audience you're working with.
Much of this is about engaging your own positive mindset and presenting with a bit of flair. Some days thing takes effort! What can you think about that can lift your own mood? Adding some of these elements to your prep for a session, or even as the limbic opening to your session helps bring you into your most positive mode of thinking.
These things could be related to your customer. Perhaps you admire or know some of the people already. Perhaps they share a name with your best friend.
It could be some kind of shared hobby or holiday destination. If you don't know your audience well, you could fall back to a fairly common relatable dream or passion. By expressing these things and incorporating into your presentation, you will help bring your customer into their most positive frame of mind as well.
Passion goes beyond your natural preferences and how much you personally like the topic you are presenting on. Passion is something that helps you feel personally motivated and engaged. Passion is about you being excited and enthused. Passion is a feeling you need to evoke!
For your passion to be infectious, you need to engage it at the right level. You can show passion and enthusiasm for very sombre topics, by showing you are considerate and concerned about the customer or audience listening. To judge the level, you should understand who you are presenting to, what kind of preferences they are. If they are a young audience that you'd as likely meet in a nightclub as at the workplace, then you could consider some music or theatricality as part of your "act". For some audiences more into sport or other hobbies, you could use some metaphors or anecdotes that relate your solution to some of these things. The more you know your audience, the better a match you can make.
In using these kinds of additional things, you don't want to detract from your main point, but you want to enhance it. Your product needs to be front and centre and positively related to your additional elements. A dry subject like taxation though, could be likened to a game of golf. You could talk about bad parts of their current solution as bunkers or water traps and your product gives you strong ways around them.
I like relating to the rock stars in my team or on the customer side. If you can help the customer to think of their team as rock stars for the way they solve problems (or that they will be rock stars with your solutions) they start to think of that positive future mode and feel good about it.
By adding an element of passion to your demos and presentations, you help bring out the best in yourself. People will relate to you better due to your positive mindset, and you'll be less put off by difficult questions or objections. Customers will want to see the best in the solution and not look for the gaps or weaknesses.
Bring your PASSION and you will be a better version of yourself.