First we strain ours when we put it in the pot for boiling, using one of the wool filters that we had originally bought for maple syrup.
Second, we filter it using the same type of filter, as we do the final boil.
After that we do not filter again, when it's light in color there's not that much sediment.. and we are ok with a small amound of maple sand at the bottom of our bottles.
When the syrup is dark in color, we let it cool and let the sediment settle to the bottom. We then pour off the top part, the best we can, reheat and bottle. Again it will leave some maple sand at the bottom.
We use to filter it at the end with the wool filters, but you just lose too much of the syrup that way. - we only make anywhere from 2 gallons of syrup to 7+, depending on the year, the amount we have left from the previous year, and our energy level at the time.
Hope this helps.