Actually, the small paragraph you've written here is a good start. Why not pop that into Notebook? :)
If you're lacking ideas, just think about something that happened which amused you, perhaps irritated you, or at least make you think.
There is no dearth of writing topics in the IELTS/TOEFL preparation material, so have a look at the many websites available and even try doing one of the writing tasks as practice.
Just a couple of paragraphs are all you need.