Yes, you can and there are a few ways to do this. Are you using an Email program or a default program? The email program has the ability to add tests built into it natively, while with the default program you'll have to use a Random Sample.
You'll want to:
1. Create an Email Program
2. Create your email and add to the Email section of the program
3. Click into the "Edit A/B Test" area you see in the lower, right corner of the above pic
4. You'll then see this, where you can determine your A/B test criteria and the percentage to test before declaring a winner
Thank you for all your help everyone!! So just to confirm, I would need to wait atleast 4 hours before the winning subject line could be sent?
I usually send my emails at 6:30 am, does anyone have a best practice on how/when i could set up my test, so i can try to send my emails around the same time?
Correct. You must wait 4 hours at a minimum (the only caveat is you must wait 24 hours if you would like to use Marketo's engagement score as your winner selection criteria). Our team typically tries to schedule tests 24 hours in advance so the email winner will still send at the time you defined.