You first need to apply for a google adsense a/c - if you have a website it shouln't be do difficult to be accepted but may take a week or two, If not you should write a few hubs first then submit the url from your profile page - again this can take a little time. Once you have a google adsense a/c you just input your adsense publication no. - go to your 'my account' tab (hubpages) and click on the earnings tab then click configure to enter your details/follow instructions and thats it. Hubpages will then automatically start to display google ads on all your hubpages - you earn money everytime someone clicks on one of the ads on one of your hubpages - google pay you directly when you reach a threshold amount on your adsense amount. Mind, you may only earn a cent or two per click (can be more though) and only a very small % of your visitors will click on your ads so you will need lots of hubs and lots of traffic to make significant money from this method alone - takes alot of time from what i gather from most others on here.The hubpages learning centre aswell as other hubs and existing questions and answers and the forum etc will provide you with more detailed info on this matter.Good Luck and welcome to hubpages.You should also consider joining Amazon Associates and the hubpages ad program to further boost earning potential on hubpages - again you'll find all the info you need by searching hubpages and using the learning centre.