Offline and online has its advantages and disadvantages. My recommendation is to use both methods for recruiting new members.Offline you can create your own business cards and flyers and leave them in various places, you can put an ad in a magazine, you can advertise your business on television or radio.
Online, you can use social network sites to advertise, you can place your link in various forums.
For this reason, I recommend you to try both ways and see which gives you better results.
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