I recieved this question recently.
I do have a question...right now, my keywords are expensive, and I do not have a huge daily budget to work on. I know the goal is to have your ads running 24/7, but until I can get the keywords down in cost using your strategy....is there a time of day that is better than another to run google ads?
I personally don't schedule ads to run at certain times of the day. Mine run all the time.
Using that feature correctly requires you to have lots of data on clicks and conversions. The idea is that you spot a particular point in the day where you are getting more conversions, then you target that time of day.
If you don't know a specific time to target based on data, then it likely won't help.
The only broad timing decision you could make is if your product or service is geared toward a particular geographic region. For example, suppose your website is geared toward North American consumers. You could elect to run your ads only between 8am EST and 9pm PST which are the prime hours for American consumers to use the internet.
This would prevent your ads from running during prime hours in Europe or India. It might also prevent robots running overnight clicking your ads.
I would recommend controlling your spending with the daily budget. Set your campaign to show ads as quickly as possible, and let them shut off when the daily limit is reached. You can collect data on the clicks you do get and split test to improve your sales copy and get a higher CTR. Eventually that will reduce the CPC and allow your ads to run longer.
In addition, you can also improve your ads and landing pages to increase quality as my guide recommends. That will also lower your CPC.