Most of the answers here don't really deconstruct your gap so let's break it down.
All traffic & ultimately sales comes from the convergence of two factors: impressions & conversion rate.
You've mentioned you've got a 7% conversion rate off your landing page, great, but what about off your traffic sources?
Is the problem that you're getting in front of people and they aren't visiting the landing page or is it you aren't getting in front of people in general?
If you are getting in front of people but they aren't taking action is it could be several issues:
- Is it the right people?
- Is it the right message?
- Is the impression clearly communicated?
- Is the next step clear?
- Is the context of presenting it right?
The best results are going to come from understanding the breakdown so we can address it.
Blind advice like "use SEO" is stupid when people don't know what your product is, who your customers are, etc.
If your problem is you aren't getting in front of enough people then it's a different challenge but maybe an easier one to solve. You get in front of people by paying for it through one of three channels:
1. Paying for the impressions (this could be direct or indirect)
2. Investing time
3. Leveraging relationships
Usually, the second is only useful when you're getting started or have a very high ticket complex sale.
The first is only an option when you've got a budget and/or you've got a funnel that immediately covers the cost to marketing.
The last takes longer if you don't already have strategic relationships and the variables are typically less within your control. This being said if you lack a budget this is probably the most efficient way to spend your time.
To do this you've got to start by identifying who your target customers are and therefore what groups already have access to that market then what those influencers would like in return and begin building the relationships through a concerted campaign.
Again, start with the gap analysis.