Well I can't find it but it's really simple.
First off you need a home that's big enough to fit a heater.
If you want two tanks that you can cycle you'll want to buy a couple of 3 gallons or larger. 5 gallons are nice. Here's a particularly good 5 gallon
. or you could go with this one which is glass
; I have that one.
Then you'll want to read up on cycling here.
While cycling you'll either want to buy a liquid test kit and change the water before the ammonia levels get above .25 (where the bacteria actually die and it burns your fish like it is now, although you ammonia levels are much higher by now) or you could do partial changes of 25 or 50% every other day and get your water tested once or twice a week at your local petsmart or petco for free. They'll tell you your levels.
What you're looking for is a boom in ammonia, then a little bit later a fall in Ammonia at the same time that you get a boom in NitrITEs, then later on a fall in NitrITEs and a boom in NitrATEs.
When Ammonia and NitrITE are 0 ppm and NitrATE is above 0 and below 20 ppm then you're cycled. You'll want to do a 50% change once a week after that.
Keep in mind though, it could take over a month to cycle with your fish in their tanks.
Now HERE'S the directions for a 100% water change:
BEFORE YOU DO ANYTHING to make things easier on you and to make sure that your water is completely dechlorinated:
You'll want to buy 2 or more gallon jugs of water at your grocery store (they tend to be less than a dollar each) and then empty them.
Then you'll want to fill them with tap water.
Next add the required dose of water conditioner (I recommend Seachem's PRIME. It costs about 9 dollars for a small bottle BUT you get more water conditioner out of that tiny bottle than you do out of bigger ones because it only takes 2 drops to dechlorinate and treat 1 gallon of water. Really good bang for your buck) to each jug.
Next let it sit for at least 2 hours to dechlorinate or over night (I prepare my water the night before as it's easier on me that way. makes water changes faster) to make sure that it dechlorinates.
After the 2 hours or overnight period you go to your jugs and then tap and knock on the sides to make sure the bubbles of chlorine gas move to the top and escape the water. This usually takes me 5 or so minutes.
If you have a heater in there with them unplug it.
Wait for an hour or so until the water has cooled down.
Scoop your bettas into the cups they came in and then pour out water till the cup is only half full.
Take the bowls or whatever to the sink or a bath tub and empty them.
Wash them (DO NOT USE SOAP, that will kill them and make sure there's no soap on your hands) with only hot water scrubbing or rubbing the sides of the enclosure to make sure it's clean.
dry them with a paper towel inside and out.
place them back where they were.
Fill the enclosures with your pre-treated water from the jugs after tapping said jugs to make sure you've gotten rid of the chlorine gas.
Clean your heaters with hot water while scrubbing them with your hands.
Dry your heaters off with a paper towel. (so that you don't mix water with chlorine in it with dechlorinated water)
Put them back in your enclosures and plug them in.
At this point you take the cups with your bettas in them, take their lids off, and put them into their respective enclosures to float them in their new water.
As the water in the tank heats up so should the water in the cup this will help acclimate them to the temperature.
To acclimate them to the water you'll have to dip the cup into the watter just slightly to let little bits of water in every 5 minutes.
After 30 or 40 minutes your water should be back up to 76 - 82 degrees (wherever you set it) and you can let your fish swim out of the cup and into their enclosures.