How should i adjust my street bike for it to be like bmx?

Question

what should i make my seat and handlebars please be detailed

Answer 1

There are also different kinds of "street bikes."  Not enough information in your question to give a useful answer.

Answer 2

there are a few different types of bmx, it depends what sort you were after.

do you mean just an all around single speed bike because that it just the hub at the back and the sprockets.

but if you were after a specialized bmx there is different things to think about

park bmx's are for skatepark they have bars in line with the forks, and the seat usually at an angle pointing to the top bar on your bars

vert bmx's for halfpipes have generally bars a fair bit forward and the seat the same as park

dirt bmx's are designed for jumping dirt jumps and normally have their bars alot further back than most other bikes and there seats are generally bigger and flat