Hi Sean,
Cycling is a bear for everyone. You need to have your filter up and running (don't change any media during the cycle). You can do a cycle with fish or without. Guppies are a good choice as Lea mentions, this will be your ammonia source. Their waste becomes ammonia and as it decomposes, it becomes nitrite (bad bacteria), then nitrate (good bacteria) - otherwise know at the nitrogen cycle. In a new tank, you will first get an ammonia spike (the ammonia level will jump up). You will need to monitor this closely because ammonia can/will kill your fish. To control this, do a 20% water change daily, until the level drops off. At this time, you should see nitrite levels rise. This too can kill your fish, so treat same as ammonia. It is also not uncommon to see your tank form a white murky appearance. You can do daily water changes to handle this as well. Finally, you should see your nitrate levels rise and the others fall off. A cycle can take from 2 weeks up to 2 months!
A fishless cycle means that you will add an artificial ammonia source like fish food. Just add a little fish food to start your cycle, then you will need to add more as described in the fishless cycle. It doesn't take a lot.
As far as your sand, you can also do 20% water changes to help clear the water. Make sure to use a decent dechlorinator for water changes. (Aquasafe, AmQuel+, or Prime are some good ones)
Does this help you? If you have any further questions, don't hesitate to ask.
