It's not easy to put yourself into someone else's shoes (hopefully they're the same size!). All kidding aside, this website does a good job of simulating what it's like to read with dyslexia. The letters continuously move around, making reading difficult and time consuming. Although it's not exactly what someone with dyslexia experiences, the website can help people better understand the challenges that nearly 40 million American adults face.
See What It's Really Like to Read With Dyslexia