Forums and threads such as these were of great help when I was planning my trip to Sri Lanka so I thought I should pay back the favour and leave a post here with some advice. FYI I travelled to SL with 3 other friends over Easter this year (April 2014).
I’m probably repeating what others have already said here but a good insect repellent is essential. As are sun protection, a hat and sunglasses. I’m used to the sun as I live in a country with a Mediterranean climate where temperatures rise well into the 30s in summer (and autumn sometimes). I was still burnt to a crisp on the one day I forgot to put on sun protection. Pack aloe vera as well. Something I did not read about in any forum is that, if you’re visiting Nuwara Eliya, motion sickness pills might come in handy. I don’t usually suffer from motion sickness, but the drive up to Nuwara Eliya did make most of us feel a bit queasy. Finally, if you have to be at the airport during rush hour make sure you think ahead. As in most cities, at that time, the traffic in Colombo comes to a complete standstill.
We only stayed in SL for 5 days so we thought it best to hire a driver to be able to get from one place to another as quickly as possible. The driver we used was Lalith Chaminda (from Shan Tours). He was great and I would totally recommend him, but I don’t think I can go into detail re our experience with him here; when I did that in my last thread, it was deleted. Just look him up on FB or else message me here and I’ll forward his details.
Sri Lanka is a beautiful country. If you’re planning a trip there, enjoy!