Well, that's the part where you usually either get over several years of "learning by doing / trial and error" or you pay to get the mentoring (including the first part but you save yourself several years of unnecessary "figuring out yourself").
Let me help you out a little bit.
Everyone loves to buy but no one likes to get sold to.
That means that you need to figure out a way where the first thought of the person is not "Ah, another person who wants to sell me something".
So you need to start a conversation by showing interest and also leading the conversation with follow-up questions. Be curious, ask questions, and add your own thoughts and opinions to it in such a way that the opposite person vibes with you (stay authentic!).
While building up your relationship and trust, you adjust your questions to find valuable information that will lead the conversation toward your goal.
If you asked enough questions, you can put a discovery question (a first test closing) with a question like "Well, if you could find a product/service that has X, Y, and gives you Z, would you be interested in it?"
If the answer is "yes", you can pitch your product/service and continue in that direction.
If the answer is "no", you can continue the analysis like "Oh, interesting, what exactly is missing out so you would be interested in something like that?" and keep continuing like "What else does it have to provide?"
Conclusion: People will have excuses like "No time", "No interest", "No money", etc. just as a sort of protection mechanism but none of them is a problem if you have something that really fits the person's needs.
I have a box here, it costs 1000$, would you buy it?
Let me ask again: I have a box that contains a 1-carat diamond, it cost 1000$, would you buy it?
You probably wouldn't buy it on the first question but the second one suddenly changed everything. Suddenly you *see* the value behind it (in the box) and are willing to pay the price.
That's your goal in sales.
What is something valuable for your client and how can you deliver that to your client?
Like in any type of business, you need to master the art of closing.
What you need is either a sales mentoring or someone who went through the process and can take that part for you. That way you will be dependent on the third person and you have to pay a huge chunk, so take that into account. Without going through the process yourself, you most likely won't know if someone is actually good at it or burn down your potential clients for the sake of having a lucky hit and getting a commission.
Conclusion: Invest in a sales mentoring.
That will be extremely game and life-changing in every area of your life and you can sell your art to anyone.