I am using Bing PPC to a presell which promotes an affiliate product. I have a number of keywords which I'm testing but would like some help with the process.

Obviously some keywords will work better than others. However....

When do you decide that you should no longer use a particular keyword? How many clicks?

Also, how do you know if it's your presell/content that needs changing, and not the keywords?

For example, if 5 out of 20 keywords are performing well, is that good? Should you focus on these 5? Or should you aim for more, by changing the presell content, headline etc.

As you can see split testing is something I don't have much experience with...

I suppose in an ideal situation, you could split test different landing pages, with different ads and keywords at the same time.

But I would need a lot of money to test with, plus I've also read it's best to split test one thing at a time.

Would appreciate any feedback...