How can I increase my sales?

Build a sales pipeline. Get the basics right. If you have been in business for a few years, you will have a good number of customers in your sales invoices who have used you before, like what you do, and are pleased with the products and/or service you provide. Think of ways to get them to buy from you again, or buy from you more often, or refer friends to you. The best form of advertising is referrals.