Question about fire blast and phoinix flames

Hi there, i do have a question about the rotation of a fire mage. Do we use fire blast or phoenix flames in order to achieve heating up outside of combustion or we scorch / fireball until heating up and then we use fire blast and phoenix flames?

Fireball to heating up, then fireball, fire blast during the cast, then pyro as the fireball finishes. The pyro and the fireball hit at the same time giving double chance of heating up and a chance of hot streak.

Pheonix flames is mainly kept for inside combustion in single target.