how can i adjust my relio oil burner?

i have a old relio but it wont run properley i have rebuilt it and it will light but i get tons and tons of soot and thick black soot i have wound the pump adjust screw out but need to know which way is weakening the mixture is it screw in to pump more oil or screw out to pump more oil i dont have access to a set of gauges so am doing it by sight as best i can i have 6 kids and a wife who is off work ill so dont have enough money to get a repair man in!!! any helpp will be greatley appreciated