Apart from voting in elections, individuals can become involved in political parties by:
Political parties are usually more successful if they have large, active memberships and can attract donations from supporters and party members.
Anyone can join a political party. The membership fees for the main political parties are quite low in order to attract as many people as possible. At election time there are rules about the amount of money parties can spend.
Political parties invested heavily in their websites and social media, to improve their communication with voters and supporters. The SNP have used social media particularly effectively to support their election campaigns in 2015 and 2016.