on benefits looking at going self employed

Hi all need a ittle bit of advise please.

I am currently in receipt of hb and working tax credits as i do 16 hours employed.

I am seriously considering going self employed but worried how this may affect my current situation. I am looking to still do my 16 hours with present employer until i was in a position to quit my current job and do the self employed work full time. In the mean time I would use a sub contractor to do the work until it reached a stage it is viable for me to do it. As I would not be taking any money out of the business and would not really do any work, I would not be profiting from this would my current situation be affected in regards receipt of hb and working tax credits?

Thanks in advance.