There is no set distance or amount of walking or even a guarantee that walking will make you dilate. I was 1cm dilated at 35 weeks and still 1cm at 37 weeks even though I was walking everyday..i after that I gave up walking daily because of the pain it was causing and finally at my 38 week check up i was dilated to 3cm
I am currently 38 weeks and 3 days right now and have been 1cm dilated since my 37 week check up . I walk 30min to an hour or more everyday and am still only at 1cm. My Dr said i could be that way till i go into active labor . Hang in there .