To migrate from a MySQL server to a big data platform like Hadoop, there are several steps that need to be followed. Firstly, you will need to export the data from MySQL into a format that can be easily ingested by Hadoop, such as CSV or JSON. Next, you will need to transfer this data to your Hadoop cluster using tools like Sqoop or Apache NiFi. Once the data is on the Hadoop cluster, you will need to create the necessary tables and schemas in a distributed file system like HDFS or HBase.