What simple strategies can I use to attract new clients in the IT/Computer service industry

You don't have to keep clients waiting for a long period, entertain them by telling them about new things you saw on the web like job adverts, technology etc, have enough service providers.

1. To Attract and sustain, you will have to tailor your product to suit the client segment you are targeting.
2. Communication plan and campaign must built around their needs and strategic objectives. Let me know if you require further clarificaitons

Be value-add. Don't sell your services but instead solve problem. Take an important current issue or challenge, solve it, and share it with others on social media platforms. People will organically attract to you and your brand if you look to solve people's problems.

Attend forums in your industry to network, get a better feel for problems that you can solve, and to identify potential future clients.

I agree with the above advice around identifying non trivial problems and offering solutions is the only real way to grow your business. I would only add that the IT/Computer service industry is a very large market with many large incumbents that make it hard for a smaller business to stand out and succeed unless you have pre-existing relationships with influencers and buyers. In a large market there are always smaller submarkets (narrow verticals) that are poorly served by large competitors. The best way to stand out is for you to develop expertise in one of those narrow verticals and grow from there.