OK I got too inspired :-) Here is my check-list to find a perfect freelance designer.
(Portfolio: Branding)
- is everything consistent? Are design decisions (colors, fonts, stroke widths, tone of voice, etc) applied consistently throughout all visual elements you see?
- is there a touch of humor? Do you nod / smile looking at the branding? (Not required but always a good sign).
- are there descriptions in the portolio (not just pictures)? Are they clear? Did they mention what client's problem they solved and how? I believe clear writing is as important for a designer as visual skills.
(Portfolio: Interfaces)
- do interfaces look usable? Are they presented not as a standalone screenshots, but as a coherent system / flow? The designs may look pretty but be awful at interaction.
- how close the screenshots are to real life? No Lorem Ipsum?
(First contact, setting expectations).
- is the designer good at self managing? Ask something like: "We need this and that, how would you work on this project?". Together with time and cost estimate, ask for the expected workflow. If their response includes things like "define responsibilities; interview stakeholders; assemble and discuss moodboard" - definitely a good sign.
- do they have a template agreement? Does not matter if they don't, but if they do - a good sign.
- do they care of how the results of their work are used? In case of interfaces, how do they go about handing off the work to developers? In case of marketing, do they actively ask about marketing needs and make sure the provided materials are convenient to work with?
- do they respond quickly? Is the tone friendly? Is the communication clear? There are many great designers out there. The challenge is to find one that delivers reliably and does not make you struggle along the way.
(Small test project)
- did they meet the estimated deadline?
- was the quality of design good enough?
- was the communication clear and timely?