No formal education is necessary to become a galley steward, though a high school diploma is generally preferred and a college education may further increase your chances of getting hired. The best way to become a galley steward is to search for jobs from cruise ship companies, yacht companies, or other businesses that run ships and find out what specific qualifications are necessary. In most cases, experience working in a kitchen, either on a ship or on land, will be highly preferred, so you may want to consider working in a restaurant to get some job experience.
Some companies will require that you speak more than one language fluently if you want to become a galley steward, since many such jobs are on ships that will travel all over the world. You can increase your chances of getting a job by studying more than one language in high school or by taking college coursework after high school. If you are bilingual and have some kitchen experience, your chances of getting hired rise exponentially. Be sure to research each job description carefully to find out what other qualifications you will need to become a galley steward. If a company requires certain specific qualifications that you do not possess but may be able to obtain in a reasonable amount of time, try to do so.
Prepare yourself for life on a ship by taking frequent boat rides. Many people find they become seasick when they are confined to tight work spaces on a ship, so if you want to become a galley steward, you will need to get used to the common motion of a boat. Rough seas do not mean you get to stop working; you will need to be able to navigate a kitchen even when the boat is rocking, and you may end up sleeping in tight quarters with other employees as well. Some companies will have physical fitness requirements to help you deal with life on a boat, so be sure to look into such requirements if they exist.
Some boats travel into international waters, which means you may need to obtain a passport in order to become a galley steward. A criminal background check is also likely, though if you have a criminal history, you will not be discounted from consideration for a job. Some companies have age restrictions as well; very often a candidate must be 18 years old or older in order to qualify for a position.