Trademark rights are gained by using a mark associated with a good or service. If you start using any mark (word, phrase, symbol) to indicate the source, the mark will have common law trademark rights. If the mark is registered with the federal government and approved then there are greater rights. If someone uses a mark that is confusingly similar to another’s, then there is trademark infringement.
All that said, it is usually a good idea to get a trademark search performed before using a mark because others may already be using the mark, or in the processing of registering (or already registered) – or something similar to your desired mark. The phrase you are wanting to use as a trademark is popular now so others may be doing the same as you, therefore, trying to gain rights without having too many collateral problems might be your goal.
Consider consulting with a trademark attorney to assess the particular facts to your situation. The attorney will guide you on how to gain as much as you can from your idea.
This answer includes generalizations and there are many caveats. This answer does not form an attorney client relationship.
