Ians, before you do anything, imho the floor will
not be dry yet! Ideally, you need to wait anything up to 6 months for it to fully dry. I work for chain of family owned decorators merchants covering the south of England and we get asked this every day it seems.
Firstly, if you have 'floated' the floor, ie made it smooth, you'll need to either use a adhesion primer first or acid etch/scarify the surface so the paint has something to stick too. Then after that, your first coat if you use a single pack product, should be thinned 10% by volume with (clean)white spirit if you use a solvent product or the same by (clean) water if water-bourne. Followed up by 1 or 2 full coats leaving each coat to dry as per the instructions on the can! Bear in mind that you will need to not use the floor for upto 7 days after the final coat to let the paint fully cure, this will ensure you get the maximum lifespan from the product.

To apply the paint a quality roller will make it easy and a new one for each coat is advised.
I notice that you're in Reading, we have a branch in Maidenhead who'll give you good, solid guidance on what to do and what product will be ideal for what you need. Hope this helps?
