A trust can be created in 2 ways: during your lifetime through an Inter-vivos trust, or through a provision in your will- a Testamentary trust. There are pros and Cons to each of these types of trusts, however, the biggest con of the Testamentary trust is that you still go through probate.
Your trust could be also be revocable or irrevocable. A revocable trust provides the most flexibility because it allows for changes to be made to the trust fairly easily. An irrevocable trust however, provides more protection. Irrevocable trusts keep your assets out of the reach of creditors and claims that may be brought later in life.
Lastly, your trust still needs to be funded. Executing a document that creates your trust is only just the beginning. You must then transfer the assets to be contained within that trust, into the trust for it to be fully effective. Otherwise, it won't function when you need it.