When you are paying for coaching, you want to make certain you are maximizing your coach's knowledge.  But to get that value and to create the foundation for a strong athlete-coach partnership, you need to pitch in. How an athlete can do this? COMMUNICATE! 
What does that look like?

• Training Peaks: every workout deserves a comment. Even an easy run, your comment can be short and sweet but it gives your coach a sense of how you are feeling.  If the easy run was a struggle, this alerts your coach that you may be tired or have something else going on.  For the key workouts ie: Bike: 3x 20 min at 80%.  Take the time to extract your intervals for YOUR sake as well as your coaches.   Put in Training Peaks 1: xx watts, 2: xx watts, 3: xx watts.   This allows both of you to see how well you executed the workout. Sure, as a coach, I can go and see it, but I want my athletes to understand their execution.  If you don’t have a coach who reviews it, do this for yourself, see if you are executing as planned, record when you are feeling: great, tired, frustrated. Capturing this feedback through comments will give you insight into how everything is going.
  
• What’s Happening:  Life throws curveballs and don’t be afraid to reach out when you are feeling sick, you have issues at work or at home.  Life situations affect your training and racing and, and as a coach, I like to know what may be affecting training. 
• Race Plans and Race Reports:  It does not matter if this is your first race or your 75th.  Write down your race plan in details: the time you wake up, breakfast – figuring out calories and hydration, swim/bike/run goals, times, pacing, watts, strategy,  even detail the nutrition for each leg.  This helps you plan, pack and execute.  Race report, write it and put in Training Peaks, it will be there for years.  Detail what you did and what worked, how you felt, what you wished you did different, etc.  The day after your race this is clear but months or years later it is not.  It’s easy to think you remember that amazing race and how you never bonked or felt like quitting but in reality you had many ups and downs yet the outcome was stellar.