Citizens of all other countries need a passport and a visa to enter Solomon Islands. Citizens of many countries can get visa on arrival, while others need to apply in advance. Check in advance to know what you are eligible for and plan accordingly.
The climate is mostly the same through the year. It is very humid with temperatures averaging 27 degree Celsius. Check the temperatures in the region that you plan to visit as there are a few places which experience extreme temperatures at times. November to April is where it rains more than usual while June to August is relatively cooler. The cooler season is also when most travelers visit the country.
The official currency of the country is the Solomon Islands dollar (SBD). There are ATMs across the country where you can withdraw local currency or you can exchange at one of the many forex places. Australian dollars are accepted in a few hotels and establishments.
Malaria is still quite rampant in the region, so it is advisable to carry adequate medication and mosquito repellants when you go. You should use mosquito nets while sleeping and keep yourself covered during dusk.
Comprehensive travel insurance is required when visiting the country. As theft is a major issue, avoid walking alone after dark and stay away from very crowded places as much as you can...