"Go-to-market" can often get over-simplified to mean "product launch". Once the big splash launch is done, there's little effort put in to the ongoing work needed to continually take a product to market. What's your favorite "drumbeat" tactic for continuing to promote your product/feature after launch day.

HI @William Chia258! In my previous company we built an online implementation use case library (situational how to's) that we used for two different types of engagement to increase product awareness and adoption.

1. Situational in-product targeting. When a customer performed a certain action without using new product/feature (we know customers always find a way to do workarounds :)) we prompted a pop up in-product with an explanation why should they use the new prodcut/feature, with a link to the use case. Here we had good results, up to 8% of increase in new product usage from the ones that read the notification.
2. Contextual targeting - we had our customers divided by different industries. Then we'd segment them and then send them  mentioned use cases that were tailored to their industry. Depending on their activity inside the tool, we'd send it either via email or show the notification in-product. 

Base for this was the implementation of good product analytics. 

I'll go first - my favorite post-launch tactic to continue a drumbeat of marketing is to gather and tell customer stories. Hopefully pre-launch you've had a rich beta where you gathered great customer stories, but certainly post launch is the time to talk to customers using the product in the real world. 

On customer calls, PMs, designers, and engineers are going to be listening to users to understand what features to build next and how to create a better workflow for the user. PMMs should be listening for the value the product/feature brings. Does it save time? money? decrease risk? Gather these stories and tell them often. 

It doesn't need to be packaged as a formal case study. Other avenues are: 

• sales cheat sheets (example385) for reps to know and tell the stories often
• presentations/pitch decks
• social posts 
• customer interview blogs
• customer guest blogs
• customer video interview videos 
• on stage at a user conference (even better to have the customer on stage to tell their own story) 

I'd add that this is why it's so important to set longer term adoption & usage goals for any product launch. If all of the goals are launch period related, it's very easy for things to fizzle out. But creating joint adoption goals with PMs and marketing means you have to continue the momentum with a lot of the things @William Chia275 mentioned in his response.

I'll agree with Josh Mendelsohn303 and William Chia288 and also add another opportunity I use to continue to promote features well beyond launch is to package them up with new and upcoming related features to continue to surface the great feature we launched a while back and also to tell a much greater story of the solution we offer...

For example, if we launch a new capability to automate an account set-up within our platform, then months go by and we launch a new feature that helps our customers QA the set-up of their account, then I would package the two and tell a story around how we help automate all facets of our customers journey, from account creation to quality assurance, at scale. So customers never forget the value we bring.