Provide positive and constructive feedback (that is not perceived as controlling).
Provide opportunities to experience success (make it easy/easier).
Reinforce (instructional and positive) self-motivational statements (= self-talk).
Formulate appropriate goals: not only outcome/performance goals but also process goals (how to do it), concrete enough, from short-term (over mid-term to long-term, difficulty level that motivates client
SMART (Specific, Measurable, Adaptable, Realistic, Time bound) principle is under fire because it missed the aspect of process-goals - "how we will do things".
It is more important to focus on process > performance > outcome