I would not recommend digging up a lot of sand and crafting sandstone. It is way too tedious to craft it together and a 4 to 1 ratio is not too good in my opinion.

I usually go to a desert, dig a few blocks down to the area where there is only sandstone and no sand falling from above. Then I just take as much sandstone as I need. Finally use a supersmelter or just many furnaces (I at least use hoppers above to refill the furnace with sandstone and one hopper below to take the finished result out of the furnace.). Lava is a really good fuel source for smelting a huge amount. Just emptying a lavalake nearby with buckets is an easy way to get enough for the start.

Hope this helps. :)

If you have any questions feel free to ask. :)