I guess this is my area of expertise. I've been rotating credit cards for over 20 years now. It's not for everyone, but it can be very lucrative. If done properly, it will not have have a negative effect on your credit score. Mine is always well above 800, one month I even hit the max. Couple rules...
1. If you cannot control your spending, don't play the credit card game.
2. Do not apply for a credit card more than once every 6 months. I tend to wait for month 7 or 8 to be safe. More than that can mess with your credit score.
3. Do not carry a balance.
4. Keep the amount of credit used on any given card below half of your available credit on that card. Even if you don't carry a balance, having too much credit used can lower your credit score. You can pay down the card multiple times a month if necessary.
5. Don't get your spouse a card for your accounts. Chase started cracking down a bit a few years back and rejecting applications even if the spouse was not the primary cardholder.
6. If you have a spouse you can double you fun by alternating who gets a credit card (also works if you have a company).
7. Read the rules on how often you can apply for the same credit card and be allowed bonus points. Example, I think you can get a new United Card bonus every two years. Of course they won't give you a card if you already have one, so you will need to have cancelled at some point.
8. Cancel your card before or just after they charge you an annual fee. If you're waiting for the end of year bonus, most cards refund your fee if you cancel shortly after the fee is charged.
9. Keep track of when you get a new card and when you cancel it. You don't to screw up and get approved but not be eligible for bonus points.
On to the fun!
One note, I don't care about the APR at all since I have no intention of carrying a balance. I'm also lucky enough to have a wife that is also a saver type like myself.
Ideally I like to have one primary no annual fee card that give me a nice bonus. For that I use the Citi Double Cash card. You basically get 2% back on everything you ever buy. So if you do nothing else other than get that card, you will be saving 2% for the foreseeable future.
I also like to have 2 no annual fee cards that get me 5% back on rotating categories. One is the Discover Card and the other is the Chase Freedom. For the next 3 months Chase gives you 5% back on gas purchases, Discover was the prior 3 months, so that been nice.
Since I have those 3 keeper cards, I can now focus on loading up on points, miles, money or whatever. The deals are always changing so you just have to keep an eye out. The funny thing is, the more you take advantage of the the offers, the more (and often better) offers they will send you. Not a week goes by that we don't get some kind of offer in the mail. I assume this is because on average, credit card users will spend beyond their means and end up paying lots of interest to the companies.
We like to travel a lot, so I often try to get the right card at the right time to have enough points for a free flight and hopefully get free luggage if needed (comes in handy for ski trips). Some airlines now require you to book with the airline credit card in order to get free luggage, so keep an eye on that. In the recent past that was less common. You can really fly all over the place for next to nothing with a little bit of work. Admittedly it's gotten a little harder keeping up enough points to fly the whole family. That's where the 2 for 1 (plus about $130) Alaska Air bonus comes in handy.
As I mentioned, the deals are always changing. There are a number of websites/blogs/forums that will let you know the latest and greatest deals. So you just need to find the right one for you. Just keep changing companies and as long as you have good credit you should get the card/deal no problem. Here are the last 20 we got (me, wife, wife's company)...
Lots of variety! As I said, it's not for everyone, but it's been great for us. Anybody else here playing the credit card game?