Disclosure: I do not receive a commission from this card.
Without a doubt, Hilton HHonor points are the easiest hotel points to generate through credit card bonuses. There are so many Hilton credit cards that feed into the HHonors system, and they are offered by different banks which makes it easier!
One of the best Hilton cards to get (and keep) is the no-fee Citi Hilton HHonors Signature Visa. I have written about it before and if you want HHonor points, this is a good card to add to the mix. Some of the high points of the card is that it has no annual fee, Hilton Silver status, and only requires $1,000 in 4 months to reach the bonus.
Citi Hilton HHonors Visa Signature Card for 50,000 Points and $50 Statement Credit – Application Link
Now, for a limited-time (through April 18, 2014), this card has received a bump in the bonus from 40,000 Hilton points to 50,000 Hilton points and a $50 statement credit after you have reached the $1,000 spending in 4 months. In addition, it will also grant you Hilton Gold status if you stay at Hiltons 4 times in the first 90 days of cardmembership (Hilton Gold is pretty easy to come by, but if this is the only Hilton card you are going to get right now, it might be something to consider).
For an extra 10,000 points (which can still be very useful for lower-tier Hilton hotels) and a $50 statement credit, this would be an excellent card to get (and even keep for additional Hilton points by spending).