Hard to really pin point the best way because there are many ways to get the job done.
Here is whats needed (not in this exact order)
1st you need a clients/a target audience to shop the music to. You can build this list with an auto responder,simple landing page and an offer (something free that you can honor weekly or monthly). Whatever you offer people to join your list make sure you are consistent with it. Heck if you are savvy enough with wordpress you don't even need to spend the money on a auto responding service. Using these services are excellent you can setup a whole years worth of work in 2 days. 100% autopilot from payment handling to track/file delivering
2nd You're going to need a decent archive of beats. To me a decent archive is at least 200.
3rd You'll have to be a trend follower or at least tune into the radio and listen to what's considered to be hot today. I do this every couple of months. Whatever is hot bite it sorry but yes bite it, understand it and make several (more like 3) versions of it. Why? Because most of your clients, if you targeted them right are going to be into a certain producers sound. Prime example, lots of artist like Lex's sound but they don't have Lex Money but.... they do have $20-50 to spend on a batch of tracks (3-4)
4th You are going to need to drive traffic to your site in order to get people to join your list. Now this can be done with adwords (expensive) or if you are smart you know how to capitalize on keywords and get the traffic free. Since we are talking about Lex let me toss out a gem
The keyword phrase “Lex Luger Beats” gets around 4,000 searches a month and the competition is low. Its nothing to toss up a site with those keywords and rank on the 1st page of google for that keyword phrase. There are other keywords you can target to get your site opt fot 10k or more searches a month
Lets stay on Lex for a little more as his tracks are simple to make. What you'd do is study his music and knock off his work. You can make 4 tracks or more a day this way because 99% of the work has already been done for you. Just take the elements and rework them. It's a piece of cake.
Now just pick an affordable price for the beats, who cares what you choose as a price right? This isn't the style of music you like creating anyway... $25.00 for 3 beats (leases). Now there will be some people that email you to talk exclusive rights and even custom material.
This business model right here can realistically generate $2k-3k a month and that's just from what you sale to the people who joined your list. It's a numbers game, if you have 5000 people on your email list and you have them set on a drip 3% are likely to buy from you sometimes more, but I keep it modest with the 3% expectation.
Me personally i hate Kpop music but guess what its easy to make so i make it and it pays well.
NOW you can sit and do whatever type of music you are passionate about without worry of bills.
I'm not a huge fan of working with artist I love getting my music on video games and tv networks. I pull down their jingle or commercial and I redo the music and send it to them.
Film schools – This is cash cow people... seriously there are tons of students out there who will pay you for music! They won't give you $10,000 but they will give you $200.00 multiply that by 15. In my area I'm one of the go to music supplies for indi student film makers I only charge them $100.00 per lease I even have a contract with the film instructors and yes I pay them a ref fee its worth it.
If you wanting to sell music via sites that's cool but its best if you are in control of the email list... The only sites I like using are pumpaudio and taxi.
Get your paper work correct as far as publishing and copyrights and please build a list of clients. You will never go broke if you have a list of people to sell to
I've gotten lots of placements with taxi as well as connections.
Last gem here. Soundclick producers, all I will say is a lot of them are not making their own material.. That is a wholesalers market right there