You have a friend starting her first AdWords campaign. What would you suggest about how to choose keywords?
Set a theme for each campaign and choose related keywords
Keep each keyword to a single word, rather than a phrase
Set a theme for each ad group and choose related keywords
Include more than 50 keywords in 1 ad group
An ad group contains one or more ads which target a shared set of keywords. You set a bid, or price, to be used when an ad group’s keywords trigger an ad to appear. This is called a cost-per-click (CPC) bid. You can also set prices for individual keywords within the ad group. Use ad groups to organize your ads by a common theme, such as the types of products or services you want to advertise.
To show more relevant ads to potential customers, group your keywords and ads into ad groups based on your products, services, or other categories.
Read more here: https://support.google.com/adwords/answer/2453981?hl=en