What is the best way to level the base for a segmented retaining wall? Can you use level string lines like a patio? Can you use forms like concrete? Also I have read some people screed 1 inch of construction sand just like they do for pavers. Does anyone do this? One more question: once you have your base pretty level, is it better to lay say a row of 5 or 6 blocks and then level them all at the same time or is it better to level each one as you go. Thanks so much for any response!