What should I do now if I want to sell my business in the next five to ten years?

We tend to either focus on enhancing strengths or trying to mitigate weaknesses. Beginning this process early rather than 2 years out gives you time to make significant changes instead of slapping band-aids on as much as possible. The first step will typically involve an in-depth evaluation of the current business. This can involve conversations with an M&A advisor to help highlight how the business would be seen at the current moment.
Starting early is a massive advantage in either approach. You can work to implement a few initiatives focused on adding real value to the business. Something like customer concentration being fixed can add tons of value but would be very difficult to do in a shorter timeframe.
The most common mistake is waiting to worry about exit value until after you have been given an unsolicited offer. At this point, you would have almost no time to enhance the value of the business. This time could be much less stressful with some early preparation.

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