Add user instructions to Incident Template

We are having continual issues with users not logging all the information we need to solve their problems. I would like to add some text instructions to the incident template with a list of information that should be included if relevant. Is there any way to add static text that is not in a field onto the template?
Alternatively I could add a multi line text field that is not editable, that has the instructions as default- however I would need the field to go across the whole width of the form (same as the subject line) - and all the user defined fields come in at only half the width of the form. Is there any way to make them wider? And longer to show all the text without needing to scroll down?
Alternatively #2 I could put default text in the description field to remind users what to include - have also tried this - but it disappears - does not stay in the template -cant set default input here?
Any other ideas please? I'm fresh out!