Big data is easy to learn but needs to follow a proper plan. Big data analysts need to have skills like Programming, Data warehousing, Statistics, understanding of frameworks and business.
Big data analysts should be very strong in programming since this is a growing field you should customize a lot of things. So, Big data analysts should be good in programming languages Python, R, Java, SAS, Hive, and SQL.
A big data analyst should know data warehousing needs to handle large and complex data. A big data analyst should have knowledge of relational database systems like MySql, MS SQL Server, Oracle and non-relational databases like NoSQL using MongoDB, Hbase, etc.
Big data analysts should learn about statistical concepts like probability distributions, hypothesis testing to make inferences from the data and also knowledge of linear algebra concepts.
You can watch this video on big data analytics tutorial for a kickstart: