I've travelled with Rayanair maybe ten or more times and I choose them because they can work out very cheap if you approach the booking in the correct way. Through the following method, I've travelled to Dublin for 2 pence return! I think the glory days of being able to do that are over but you can still get a very good deal if you follow my tips below - many of these will apply to flying with other low cost airlines too.
* If possible be flexible about when and where you want to go - the prices can vary widely - select the monthly view so you can see which are the cheapest days - play around with different combinations of inbound and outbound flights.
* If you're prepared to travel mid week it'll be much cheaper than travelling on a Friday or Saturday
* Only take hand luggage - this can be done no problem if you get the right sized carry on case BUT bear in mind that they strictly police the one bag rule - this includes handbags so your handbag must be able to fit inside your main carry on bag.
* Don't pay for their insurance - you will find cheaper
* Choose the cheapest payment method - unfortunately the only free way to book is with a Ryanair credit card.
* Keep onboard costs low - take some food with you.
You can tell you're travelling on a low cost airline when you travel with Ryanair - everything is yellow and blue plastic but you just need to remember it's just a cheap means of getting to your destination. I have had a couple of delays with Ryanair - usually on the way home (when you just want to get back)! It's ontime performance does compare very similarly to other low cost airlines though and you get a little jingle when you land if it is on time!