If you wish to make fat-balls for the wild birds, chicken fat is not suitable, as it doesn't set properly, and is not very good for the birds. What is recommended is beef dripping which can be bought from local butcher shops. Hope this helps.
I thought I'd make my own seed balls - good old Blue Peter stuff with string, suet, seed yogurt pots etc but financially found it worked out cheaper to buy a big tub of ready made balls in netting. Freed my fridge from setting them hard & insult to injury I think the birds preffered em.:( Gave up on loose seed on the bird table as lots got knocked into the earth & come the Spring I had an awful job clearing the borders of some strange greenery & grasses!
I have fussy birds, if there is such a thing. I havnt found a seed that they dont throw discard half of it, but will eat one of the RSPB cakes in a day.