Submit proposals to potential clients
A proposal is a document that lays out your intentions related to completing a specified project.
This document may be the first formal point of contact with a client, for example if you are responding to a general RFP posted online, therefore it is important that it clearly communicates your aims. Alternatively, you may submit a proposal after discussions with a potential client.
Either way, you should pay careful attention to the requirements of your client when creating, formatting and submitting a proposal.
A sample proposal template can be found here.