After I get them laid out I usually use post-it notes and mark things A1; B2, etc. and then pin the notes to the blocks/rows as appropriate. I don't have a large flat surface to work on, other than my cutting table, that the dogs don't walk on so sometimes I have to work in sections on my cutting table. I also bought 2 flannel-backed tablecloths and sewed them together for a 'design board' but don't really have a large enough wall without something in the way to hang this either.