One of the first items that most site test are CTAs.
A button is a button, what range of tests can you actually run?
- CTA text and background-color
- CTA size
- CTA label font-size
- CTA font type
- CTA border-radius (only consider if you have a substantial amount of traffic)
- CTA positioning on the page element (left, centre or right aligned)
More ideas to come soon.
More here: https://www.growthsnippets.com/