First head over to: https://app.datatrics.com/integrations/mewssystems/ and click on "install"
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After clicking on install, you will see the following prompt:
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You will need to enter your URL and Token.
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In the URL field, enter the URL used for your Mewssystems integration.
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You can find your token within mews using the following steps:
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1. Main menu > Marketplace.
2. Click My subscriptions.
3. Find the mews integration to get the access token, and click Settings.

4.Click the key icon in the upper right corner
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After entering these fields and saving, the integration has been made.