Hey there,
I did the NETT course. Its intensive to say the least. But the info and learning curve is good, in fact excellent. In my opinion you will have to do a bit of practice, especially with one or two of the advanced techniques, it will all be apparent when you attend. A board or a spare wall in a garage should do the trick.
I "graduated" 10 weeks ago, but luckily for me I was not an absolute novice, and I had already done a couple of bathrooms and splashbacks etc.
At the beginning I ummed and erred as to whether I would take it as a career, however in the last two weeks I have managed to get some contract work for a floor, and also a bathroom I start next week, in all honesty all by accident. I have also created an opportunity for a big job that I will be quoting on tomorrow. Things are looking peachy right now, I stand to have earned nearly 6K in 6 weeks if i get this big job. So i do think 30k is attainable in a year. It depends on your marketing startegy. I have the benefit of 12 years in marketing and its a big help. Darren has some excellent suggestions, but there are other routes as well. You reap what you sow.
Be aware you have to work for it though. Its no easy ride, and at times its a bit soul destroying, at first you think you will get the work everytime you quote, it really doesnt work like that. And its definately a people thing. If you get on with your customers, that will get you the job more than your price, IMO anyway.
In short, lol considering I am the king of over verbose posts, pay attention to Darren and make proper notes. And research your area. You may be over saturated in your area and that will reduce the amount of work available. "Setting up" properly as well as "setting out" properly are the most important things IMO.
Cools71