I done cert 3 and 4 (they ditched cert 4 the year after) through my local tafe ft, straight out of high school.
Applied for a casual lunch relief job st the end of the year, got it.
Enrolled in correspondance for my diploma, and completed that the following year, on my own, while working part time.
Once I was qualified I was still in my relief role but striped into whatever room/role was required.... I really wanted my own room but the opportunity never arose, got the first qualified job I applied for next and was starting my advanced diploma but left to start my family.
It was hard work, the extra paperwork to price you understand the processes was headache inducing, having worked in the industry, and knowing you bypass writing certain things down... But was worth the effort.