There are five boards (the first) on sigchan. This announcement is to let you know generally what each board is for. There is obviously flexibility in this as each board develops it's own culture.
/fit/ - Fitness and Health, this is pretty analogous to 4chan's fit, although it also encompasses mental health topics such as depression. Another addition is that anything that would belong in /fa/ also belongs here.
/fin/ - Personal Finance and Investing, this is analogous to /biz/, although I would prefer more investing than crypto discussion. Anything dealing with your own business, taxes, personal finance, and economics also belongs here.
/int/ - Intellectual Pursuits, this is an amalgamation of /lit/, /his/, and /sci/. I eventually would like to split this up when the activity warrants it.
/env/ - Travel and Outdoors, this is an amalgamation of /o/, /out/, /int/, /n/, and /trv/. Whether things that go on /k/ belong here I'm not sure yet, they seem to fit into both /hob/ and /env/ for now let's just let them in both.
/hob/ - Hobbies and Interests, this encompasses everything not mentioned related to Improvement. Want to discuss chess? This is the place, want to improve your origami? Again this is the place.
As I stated before, things cultures on these boards will be forming over time and all of this is flexible. If you have questions or want to discuss feel free to join the IRC, the server is freenode and the channel is #sig.