When to seek professional advice.

Assuming your existing company is Co. B Ltd.

Horizontal diversification
Invest in new products / service lines that serve similar customers or open new companies elsewhere. The idea is to achieve an economic scale, so that it has a greater purchasing power and reduces the general cost.

Vertical diversification
Be your own provider. Establish a company, Co. A Ltd that will supply raw materials to Co. B Ltd. Co. A Ltd will get stable orders from Co. B Ltd, so it is considered safe and secure. Of course, Co. A Ltd should look for new customers to expand their business.

In the same way, you can be your own customer. Set up a company, Co. C Ltd, which will handle the logistics (which you may be outsourcing). Once again, Co C Ltd will receive stable orders from Co. B Ltd and have to get their customers to expand the business.

The idea is that your benefit / cash will continue to circulate within the group of companies instead of "flowing".

You may consider hiring CEO / GM to lead the new business with KPI, of course.