[Koha] Expression of interest to download and use koha

Dear Sir/Madam, Mineral Resources Authority is a newly established organization that has a huge amount of geological records for the country. The library now intends to use the Koha -Library Management System to store all its records. We are confused as to how to execute the down load process. We have searched your information on the net, however it seems abit confusing. Please assist or guide us along on how we can download and start using koha. Regards and Merry Christmas. Josepha