This is an important form of networking and its main advantage is that it is completely free. If you create a good representation of yourself, those who you have provided good quality work for in the past will be more likely to recommend you to others. This is like a cycle and this will grow as the more clients you produce work for, the more people will recommend your services.
A disadvantage of word of mouth is that it is not always assured that the recommendations will spread which is why it is best to try to work for a variety of people and businesses in different sectors to help the spread of people recommending you.
A possible example of word of mouth is that you produce work for a client and they are very happy with the product they receive, then they go and tell their friend who is also needing somebody with the skill set which you have and they then approach you for the services you provide.
Conferences are where many people are in one area and you go talk to many different people to create contacts. An advantage of this is that the type of networking is usually face to face meaning you can introduce yourself better than online, you can give a much more friendly introduction.
A disadvantage of conferences is that they are not always guaranteed to be in your area meaning that if you travel, there is a high possibility that you will be speaking to someone who has also travelled but possibly from somewhere far, if you network with these people and they recommend you to someone in their area, you will then have to travel to the job.
Business cards are a great way of spreading awareness of your brand, business or services and are fairly cheap to produce. They are small cards and usually contain a summary of what services you provide followed by contact information and possibly social media links. They are useful when interacting with people at events or conferences and day to day life. A business card will fit into your wallet meaning they can be carried around everywhere and handed out anywhere.
Leaflets are a good way of networking in some industries. Some advantages of using leaflets are the cost of producing leaflets is very low and you can design the leaflets how you like them. They are similar to business cards but old more information. Some disadvantages of leaflets are that the public usually just discard leaflets posted to them and this is even more likely if the leaflets are poorly designed.
Social media is a good way to network as you can share some of the things you have produced and the potential clients can see the work you have created. They can see the quality of the work and also the style of the work, especially if you work in a specific style.
Working on jobs is a good way of networking as you will be connecting with people you have worked with and possibly could work with in the future. Something that could come out of networking like this is that if you work with someone and they get asked if they know anyone with the skill set you have, they are likely to suggest and recommend you, especially if you have a good work ethic.