How do I get bells on here

[Frogloaf]

?

 

[XinMiao]

Trade with people and just comment on posts and such being active basically

 

[AppleBitterCrumble]

^^
I amassed my tbt by doing a lot of trading (as in selling items in NL/NH for tbt)

 

[Luxen]

You earn bells by making threads or posts around the forum.
Other than that, you can also earn them from:

• Official contests (ie. if it's a participation reward)
• Official announcement threads (if the staff happen to be giving some away via a 1-time code, like at the bottom of the OP here)
• Selling/trading in-game items/services or on-site collectibles for them