Good to build one in the back yard. First year was just pressing down the snow and then spray water over it until a good crust of ice is formed before doing the flooding. Water will stay for the flooding.
Last year, bought a skate rink sheet at home depot. It really help a lot and use much less water. The rink can be kept longer at the end of season since it's white color and reflect the sun.
1/ you have to make sure your backyard if level enough. If not, try to level it with the snow you have, mix it with water to make slush will help.
2/ with skate sheet, put some snow over it and water will save water.
3/ when you build up some ice, no hurry to flood the rink as the levelling is important as it may require a lot water to make it work. add snow to low area and add water.
4/ flood the rink in evening, make sure free of dirts like leaves, dark color things in ice will absorb heat and create holes (melting the ice).
5/ get a 24" or 36" scraper from Princess Auto (on sale now). After a few skates, scrape the surface before adding water in the evening. A new sheet of ice will form nicely for the next day.
It has been a good experience, kids enjoy it very much even when it's very cool as they can get back home for a hot drink and then go out again. It'll be a lot easier to put their skates on in side your home. Just put carpet along the way to the rink. they can skate every day after school!!!