No matter what way of transportation you choose to get to this heavenly island, please make sure you comply with all the entrance regulations. You are expected to have all the necessary travel documents such as your passport, photo identification, travel insurance, visa, etc on hand all the time. Besides, there are immigration and customs forms that have to be completed upon arrival.
The visa regulations of the Dominican Republic are pretty flexible and most of visitors, namely from Argentina, Chile, South Korea, Ecuador, Israel, Japan, Peru, and Uruguay, diplomatic and consular staff with assigned missions in the country or while on duty can cross the Dominican borders just with their passport. Travelers who are legally allowed to enter the European Union, Great Britain, The United States of America, and Canada can enter the country with the same documents just additionally buying a Tourist Card for as little as $10US/ €10 which is valid for 30 days starting from the purchase date. You can buy it in any airport or seaport and even Dominican embassies and consulate offices in your home country as well as from your tour operator agents and online (link https://www.dgii.gov.do/tarjetaTuristica/EN/about/Paginas/default.aspx)
Even if your stay will be longer than a 30-day period, there is absolutely nothing to be worried about because the proportional extension fee can be paid at the Migration Department or at the migration desk upon departure depending on the number of extended days.
Visitors from other countries can always check the Dominican Republic Tourism website (link https://www.godominicanrepublic.com/about-dr/entry-requirements/) for more detailed information on how to apply for a Dominican Visa. The list of countries exempt from visa requirements keeps expanding as the Dominican Republic remains one of the most open Caribbean nations that welcomes warmly people from all over the world.