You can take liquids (including gels etc) in individual containers which each hold no more than 100ml. (Note that it's the size of a container that matters, not the actual quantity of liquid inside it. So you can't, for example, take a 200ml bottle which is only half full).
There's no specific limit to the number of containers but they must all fit comfortably inside a single, transparent, re-sealable plastic bag, approx 20cm by 20cm. (e.g. the 'sandwich-sized' resealable freezer bags which you can buy from Tesco):
http://www.dft.gov.uk/transportforyou/airtrave l/airportsecurity/requirements
As you're travelling with Ryanair, ensure that you're familiar with the maximum dimensions for your single cabin bag. (The dimensions are slightly smaller than those imposed by the current EU-wide security restrictions):
http://www.ryanair.com/site/EN/faqs.php?sect=b ag&quest=cabinbaggageallowance
Chris