When developing MLM software, the most important step is to determine the MLM plan type to be used. This is because the type of MLM plan will dictate the overall structure of the software. Depending on the type of MLM plan chosen, the software may need to track different levels of commissions or provide different methods of customer referrals. Additionally, the software will need to be able to handle different types of compensation plans, such as matrix, binary, and unilevel plans.