It is always a good thing, good medicine, to leave offerings to spirit. Offerings aren't an exchange to prayers asked for. Offerings are more of an acknowledgement, a gift with no strings attached. When you give an offering you are letting the Andedion, the spirit world, know that your are aware and reverence them. They are important to you. Offerings can be made in thanksgiving for gifts or prayers/spells answered, but generally, daily offerings are a very good way to build a relationship with spirit.
Now, what should we offer? To make it easy, you can make an offering of virtually anything! You should make sure that your offering isn't throw away stuff. Generally it should be, to the best of your ability, the best or most valuable to you that you can manage. And I don't mean monetarily valuable, but heartfelt value. Often I'll give some of what I'm eating for my meal.Just a spoonful is plenty. Heavy cream, any liquor, meat, bread most foodstuff is good and it doesn't need to be large quantities. This is an energy exchange. A small prayer helps to let them know this offering is for them.
Offerings are left outside at a special place , the base of a tree or wherever. You can have special prayer plates or leave your offering respectfully on the ground. animals may come and eat the offerings and this is fine as they are considered agents of spirit. As a person, NEVER EAT ANY FOOD THAT HAS BEEN LEFT AS AN OFFERING! This is considered quite offensive to spirit and can be dangerous. NEVER BRING ANYTHING OFFERED BACK INTO THE HOUSE! This, to spirit, appears you are taking the offering back. Again, insultive. After a night out you can retrieve your prayer plate, just put whatever is on it on the ground and you're good to bring the prayer plate back in to be washed.
You should try to make your offerings a regular habit. Quick and simple, elaborate and full of pomp, anything works and your relationship with spirit will blossom!
Blessings