Make sure that the tree that has not been sprayed with pesticides or chemicals, even years ago as the chemicals can remain for a number of years. Also make sure you know for sure what type of tree it is. Follow the above link to make sure the plant is safe. (the plant not just the fruit it bares) If you aren’t sure, just don’t use it.
To prepare the wood, many people scrub the branches or twigs in hot water first with a brush. This will help get rid of any dirt and pollution that may be on the outside of it. If any of the pieces have lichen on it, toss those out as some forms of lichen can be toxic. Some people will then boil their wood to take out some of the tannin and to kill germs. Not everyone does this however. Some also recommend a salt water scrub but again, not everyone does this.
Wash, scrub and boil your wood and allow to air dry then......
the next step would be to bake the wood. This is to kill any microorganisms or insects that may be living in or on the wood. Sort your wood to have pieces that are about the same size together and put them on a cookie sheet or tinfoil. Keep them about the same size so that they will need to cook the same amount of time. Preheat your oven to anywhere from 150-200 degrees. The lower temperature that you use, the longer you’ll need to bake the wood, but if you do a higher temperature be sure and check the wood often so that it doesn’t burn. You’ll need to bake your wood for at least an hour. The time will really depend on if you have green wood and how big the pieces are. Just keep checking the wood and when it is dried out, take it out and allow it to cool.
Store your dried wood in an open package so that even if you did miss some of the moisture, it will naturally dry out and not mold.
Take a drill and drill a hole in the end of a branch and then take a pair of pliers and twist a hanger bolt into the hole by the spot in the middle with no threads. You can then use large fender washers to mount the sticks into your cage.
I'll post pictures later.