Money is always a hot topic for freelancers. If you are low or having cash problems then I would focus on these 3 areas to figure out where you are weak. Then once you plug the gap you should stop seeing money just pass you buy and have more chances to give more value to your clients.
This is not a topic you should be scared of, I think it's a topic that deeply divides people and is the source of so much pain in almost every area of life if you don't have it.
Essentially I break it into 3 sections:
Get More New Clients
This is very resource intensive because you need a bit of luck and good timing to find the right person needing your services at the right time. But if you don't have regular clients coming back to you then you need to work on this.
This was an interesting phase as from when I started and I had lots of new clients and lots of number 3 which is clients coming back to me but I was still not really making enough to invest in better gear which was now getting to the point of everything I needed to improve was in the £1,000's. So If you are working a lot (2/3rds of a month+) and still not making as much as you need to keep growing then address if you are charging appropriately
Get More Referrals / Days Work
If you have enough clients that you have worked with but find yourself spending more time on new clients and charging a decent amount then look to getting referrals. These are the best because you are prequalified to other new clients and then you can also get in better books with the client that recommended you because they are helping someone in their circle and then you help the new person and its a win win.
Let me know in the comments your thoughts.