First things first, you have to have all your documentation in place. Make sure your passport does not expire in the next six months which is a requirement to enter the country. Bali offers on arrival visas for around 140 countries. Check the list, and if your country is one of them, you do not have to apply for a visa prior to your arrival. You will be getting a 30-day stamp to stay in Bali. If you ever feel like you need more days, and 30 days doesn't cut it for you, you can always extend this visa for 30 more days, but you will be charged. It is around USD $70 for renewal. Make sure to book accommodation before your arrival so that you don't waste any valuable holiday time looking for one. You can look into Seminyak resorts, the likes of Katamama for a cosy stay.