- Actually phone up at least one new sign up per day. Ask why they signed up, what they use it for, how it compares the the others they have used and what would they pay for - unlimited time, number participants whatever. They will try to be nice - assume they lie. most importantly how did they hear of you. Pay attention to the vocabulary they use. What you are trying to get here is your elevator pitch - but told to you by your customers "Video chat right in Slack"

- You now have some idea of channels to market - ten people signed up because of a facebook post or because of a linkedin article or a google search - so choose a channel - facebook / linkedin / SEO. Just produce ten articles or pay for ten adverts - and see what traffic changes you get - stick at it - you are looking for a channel to market. Somewhere somehow there is a way of reaching a potential audience - with a sales pitch you learnt from above you want to find where that sales pitch reaches the most of your potential audience

- pricing - this matters less than the above especially as you are aiming at busiesses - I would say Slack has a pricing norm so you may want to charge per user but aim for 30/55/75 or there abouts.

- keep trying new sales pitches, and vary the channels you try slowly.

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