like the blind leading the blind ,lol
here goes ,
Cement Backer Board, half inch Thick ,
corrosion-resistant coated screws ,
fiberglass mesh tape ,
thinset mortar,
measure an cut the board to size using a fine toothed saw ,
using a file smooth off edges ,
fit your first board , rough/dimpled front outward an screw every 6 to 8 inches,an not more than 2" from board edges ,
an fit next board next to it ,screw down ..
on the join use fiberglass mesh tape ,
an spread a thin coating of mortar over line of tape
now either tank boarded wall or tile on
if you have any probs understanding this go here
http://www.toppstiles.co.uk/3/tips/tips_backer_boards.html
hope this helps you