On arrival

When you cross the border into the Schengen area, you will have to present:

You may be asked to provide fingerprints by the border control officer, in which case these will be compared with the fingerprints provided when you applied for your visa.
As long as your visa is valid, you can travel around freely in the Schengen area, or in the specific Schengen countries covered by the visa. If you leave the Schengen area, for example to visit the UK or Svalbard, you will need a multiple entry visa.

Please be advised that if you do not travel directly from Sri Lanka to the Schengen area, you might need a transit visa to the country you are transiting in.