Formal:
* Embrace new experiences
* Explore uncharted territory
* Venture outside of your comfort zone
* Seek novelty
* Engage in novel activities
Informal:
* Step out of your box
* Get out there and do something different
* Branch out
* Go for it
* Be adventurous
* Don't be afraid to try something new
More specific:
* For hobbies: Take up a new hobby, discover a new passion
* For travel: Travel to new places, explore new cultures
* For food: Expand your palate, try different cuisines
* For personal growth: Challenge yourself, learn new skills
The best alternative depends on the context and your desired tone.