@pdehaye great to hear you are interested. I recommend watching the first half of he intro video here: Introduction Hangout for Core Data Curation April 2015 and taking a look at the guide: http://data.okfn.org/doc/core-data-curators
Then you can dive in to the datasets queue and start commenting: Issues · datasets/awesome-data · GitHub
For help just post in the core datasets category of the forum