Your mission, should you choose to accept it, is to observe and assess your environment – starting right now.
A few quick tips:
How are you feeling? (ie. Your own personal environment.) Your health (and what you wear) directly affects your performance. What clothing and footwear are you wearing? If you're not dressing for personal protection, then have a plan to stay protected with greater range (prior to leaving your home).
Do you have an everyday carry tool? If not, do you know how to improvise?
When traveling, do you have a plan? What type of transportation will you be utilizing – Car, train, plane, boat, other? Observe and plan for specific interactions relative to each transporation experience.
While in route and when you've reached your destination, what do you see? Who's there? Notice what people are wearing – is it appropriate for the weather/temperature or out of the ordinary? (e.g. Someone wearing a heavy coat or long coat in the summer, should raise a red flag.) Is any one acting erratically or suspiciously walking while covering their face with a hood or other piece of clothing?
Observe what's normal (or not) outside and inside, before and after you've entered environments (indoor spaces, outdoors, urban, rural, etc). Look up and down not just laterally. Stay alert, but not paranoid.
What's around you that you could use for protection. What can you place between you and a possible threat? Within range of your position, can you identify cover and/or concealment that you can utilize? Are you placing yourself in a position to gain the best vantage point? Where are your exits?
What are your strengths and challenges? What do need to be more effective? Seek it out, plan for it all and make it second nature.
Use all your senses, develop practices for protection, and learn to use strategic tools to increase your range of operation.