Buying UK registered car in Ukraine and need help filling in the form to send to DVLA

I want to know if it is right to fill the new keeper of the uk registration certificate of dvla with a black ink pen and I want to know how, please show me how to do it the right way. I am buying a car with uk registration certificate of dvla in a foreign country which is Ukraine, so I want to know if it is right to change ownership with a black ink pen in section 6 and then sign and date in section 8 by me the buyer and then also the seller. thanks......