One of the keys to professionalism as a freelancer is the ability to adhere to a style guide and produce work not only of a consistent quality, but in a consistent way, so that it looks like it belongs among the client's other content.
I know this is an area where I can improve, mostly due to being easily distracted by small shiny objects and forgetting what the style guide says for a particular client. Ways I deal with this include keeping their style guide reference open so I can easily consult it, or creating styles in in, say, my word processor so I can just apply the style "Clientname: Subheader 1" and move on. Some clients even send templates so you can just apply their styles--though these templates have the complication of needing to work with your software. -- Read more