When is the timing appropriate for each Boost (day or evening)?

Base the time of day you select a Boost program off the state change desired, understanding that each boost can affect your client differently (e.g. You may not wish to do a Chill boost in the morning, when their day ahead may demand a lot of focus from them - Drive or Prepare Boosts may be more appropriate). 

Information on the purpose of each Boost can be found in the Sens.ai Professional staff guide.