polysynthetic (con)langs

After I discovered those West Greenlandic sentences like Ininnukalaarniarlungaana
'The thing is, I'm going to my room for a bit', I wish to create a
polysynthetic language. I think it'd be really neat, even neater than making a
Tzeltal-based conlang... OK, maybe about as cool. :))) But I don't know where
to start. I don't know much about West Greenlandic and other polysynthetic
languages, so could someone please enlighten me?

Thanks,
--Robert