I didn't read any books, nor did I do work experience. If you do decide to, you shouldn't just do it for the sake of it. They want to hear why it was useful and not just "because you could". They want to know why you're the right candidate for the course and for their university.
In my personal statement I wrote about projects that I would like to work on in the future, issues which concern the engineering world and things I had done which I thought would make me suitable.
For example, I saw a news report saying that trains can produce as much as 90% fewer emissions compared to aircraft, but aircraft have more flexibility to go further and that studying topics in aerodynamics and materials would make me suitable to work in that industry to fix that issue. Air traffic was estimated to double in 15 years, so they need new breeds of aircraft which are lighter and more aerodynamic so that they reduce the emissions produced. I mentioned green design and how my work in college revolved around finding renewable materials to work from.
If you research the universities, you can see which industries they are associated with. Some are automotive, some are aerospace and some are things like trains, so I tried to write about all of those topics and make it link up.
I mentioned awards I had received, such as best in class and things like that. I spoke about how I taught myself 3D design and used it in technology projects (others were using 2D design or just drawing on paper). I mentioned projects I had worked on (using LASER cutters, making custom jigs, designing and making aesthetically pleasing work).
In closing, I mentioned where I want to go with this degree and where my career should take me. I spoke about finding placements and that I wanted to work in aviation.
The main point is to link it all back in. Don't just say "I did this", "I did that". Be more along the lines of "I am interested in this topic because it forms the backbone of modern engineering and, according to 'these statistics', is an upcoming area of work". It doesn't have to be a report on engineering in general, but show where you fit into the grand scheme of things. Make yourself sound interesting but also interested.