problem with trying to be your own coach is this -

a coach is required to teach you something that you don't know.

we need to  get around this definition, for you cannot teach yourself what you do not know.

we can refer to the concept of parallel of lazy evaluation in computation ,where functions that aren't defined can be referenced (but not called)...

as a coach, one can set a growth path, with vaguely defined progress goals, and somewhat less-vague real world changes - for example - 

vague -  in a few months, we'll have better BMI and muscle tone

less vague - in 6 months, we'll have a BMI that is 25 and some muscle tone that is visible.

the approach is the same, control the variables in one or two ways - eat less/ eat better / eat different / workout more / workout different/ try meditation or tai chi ...

the only way this can work is that one accumulates a series of experiment results and keep getting the power and resources to do more and more risky experiments to learn more and more, until the sequence works in your favour in terms of growth and swag