There are 4 programs available with HubPages to earn money.
1) Google adsense
If you have an ID (membership) of above affliate programs simply you can enter those IDs in "Affliate Settings" (My account --> Affliate Settings). Then 60% of time you will get revenue from those programs when someone read your hubs.
If you do not have any of this you should sign in with those programs. Kontera & Amazon is easy to sign in.