Putting some points from my side.
1. Have clear portfolio in place
2. You already have mentioned Target Market - segment it based on your portfolio
3. Plan for go to market strategy -
Marketing - online, digital, social
Sales - Appointment setting (Internal/External) and Lead Farming
4. You can use various platforms to reach out potential clients - nothing is wrong and nothing is perfect.- Linkedin, technical communities, twitter and many more
5. Conference Participation, Exhibitions adds value as you can have short but in person contact with potential clients
6. I would suggest to build Lead or Interest Generation Engine with realistic strategy and enough patience to observe,understand and fine tune the strategy.
7. References of satisfied customers plays big role in generating qualified interest and closure
8. In future you can focus on qualification, segregation and prioritization of interest / leads to ensure your organization chose right projects to build your portfolio
I have answered the platforms in pt # 4 & 5 but thought to add more context with other points.