I would build towards a goal as mentioned.
A good example would be:

trip to a nice hilton on a tropical island
churn hilton citi card every 65 days (only 1k spend) to pay for hotel
apply for card for airline that will get you there - meet minimum spend
then go card by card for transfers to that airline (like united and chase UR)

alternatively, if you have southwest at your local airport, you could go for the companion fare next time the southwest 50k promo comes upand get a business and personal card. that only is great if you have someone flying with you

I think really the best way to do it is to discover a destination and set that goal. Then you can get more specific advice and do more specific reading.