I am a graduate student from India holding a valid B1/B2 US visa. I obtained it for attending a conference. Though I applied for B1 (conference/business) the visa type on my passport reads B1/B2. The only travel I have done with the visa is for the above mentioned conference and I did not overstay. I am planning to visit my girlfriend who is a graduate student at Brown University. I have booked both way tickets and I am visiting for ten days. I am planning to stay with her (at her apartment which she shares with her friend) during those ten days. What supporting documents do I need to produce to be allowed entry at my port of entry (which like the last time I traveled is JFK), especially regarding intent of return.
Return ticket is sufficient document to show as a proof that you don't intent to overstay (of course not overstaying in first visit will be an added advantage for you). Also, bring the travel insurance copy with you and let the Immigration officer clearly know you intent of second visit (if asked).