For a person's profession, 1st of all see his education, then 10th house and 6th house.
For earning money there are 3 important segments:-
A person will do the job (written on the same page)
Rule 1:- if sub lord in the star of 10th house refers to/indicates 6th house then a person will do the job.
Rule 2:- if it indicates or refers to 7th house then business.
Rule 3:- if it indicates 5, 9 then he will do his work.
Rule 4:- if it indicates to 6 & 7th then he will do job and business.
While, predicting of carrier first of look at his/her education (4th), house of competition (5th) then check his profession, house of the profession (10th), wealth house (2nd) and also check from where he will earn money.