"Free" work is literally part of the word freelancer and you should accept that you are going to have to do unpaid work, especially at the start. The best types of free work to do are the types of work you're really excited about doing over the long term. Some examples of things you might want to think about doing:
- Offering a free high-level analysis for a potential client
- Joining meetings with the client to offer perspectives
- Writing on your own personal site or blog about topics that excite you or relate to the field you want to do work in
- Initial diagnostics like interviews or surveys to help a client assess what is happening in their company
A great twitter thread on this topic:
Stage 1: Do unpaid work for yourself
— visa is cleaning out his notes (@visakanv) July 7, 2018
Stage 2: Use that as leverage to negotiate a position where you get paid to do work for others
Stage 3: Save up enough so you can be free to do more, higher-quality unpaid work for yourself <--- I am currently here
Stage 4: We’ll see
More thoughts here