Many people have asked me about the bidding strategy i use, so i thought to explain that a bit. It may not be the best strategy but this is what i use and i am satisfied with it. I read it somewhere quite a long time ago so don't remember the reference.
I start mostly with the highest bid suggest + 0.10 CPC. For e.g if i am suggested 0.12-0.24 CPC then i set the bid to 0.34 CPC and set campiagn budget to $10. Then i keep the campaign running for $10 and don't change the bid in between. When $10 is consumed, i pause the ad and let it remain paused for 10 minutes or so. I read somewhere that Letting your CPC catch up with your CTR lowers the CPC. So at this point i check how good is my CTR, if it is anything above 0.2% i resume the ad and increase the budget to $30-$40. I actually notice CPC drop for most of my campaigns this way. When it reaches the next budget limit i pause it again to let the stats get updated. Check my CTR, if it is still strong enough then i resume the ads with budget set to $200 and keep monitoring my campaign. This method totally relies on your CTR. Higher the CTR => Lower the CPC, Keep making new campaigns with different images and headlines. You will surely see improvement in your CTR and soon you will get a winner ad copy that you can keep running for some time.
Another thing i sometimes run my campaigns only in the peek hours that is 5pm - 12pm. This also gives me better CTR and more conversions.