If something that you're doing doesn't challenge you, then it doesn't change you． We all need some normal stress in our lives, after all． So challenge the following limits:
1． Figure out what you're scared of and do it continuously．
If you're a salesman, and you're scared of talking to people personally or over the phone, now, instead of being scared and thinking you’ll fail, spend at least five minutes a day to pick up the phone and make a call． But don't stop on the first try! Eventually, you can look at fear in the eyes and say, "Go on, I'm not scared!"
2． 
Make sure this hobby is not linked to your career; you have to relax and relieve your stress while performing this． Some examples might be cooking, sewing, painting and so on． Apart from helping you challenge yourself, taking a class for your hobby may also give you extra income．
3．Set aside at least nine minutes a day for physical exercise．
 A simple 9-minute run around your neighborhood can do wonders for yourself．Exercise can not only help you maintain your regular weight, but also make you feel better about yourself．
4．Travel and allow yourself to be interested in new people．
Don't just limit yourself to your fellow travelers - try to connect with the service staff．You never know what kind of people they're going to be． Get out of your house or go online right now to book your class． 

A．You should do it continuously．

B．Someone may hang up on you．

C．You don't need to go to the gym．

D．Running in the gym may be a better choice．

E． Start to travel now and learn to challenge yourself．
F． Take a class for a hobby you've been wanting to develop．
G． You can never see any improvement if you stick to your comfort zone．