From MyBB to Xenforo


I do not have a knowledge for importing forum becose i never did this before so i need step by step tutorial how to transfer mybb to xenforo.
I buy licence and its time to fly ;)

My mybb forum is instaled in public_html on my host and that is all what i know.
I have downloaded Xenforo and what are the next steps? I download all from my host(my mybb forum) and i use php my admin for export my forum if something go wrong, for have full copy of my forum.
I will be realy happy if someone can explain, stepbystep tutorial for not make any mistake.
I saw some tut's here but to average for me :(
Thank you!