Please follow these instructions to use your Twitch Gift Card from Uquid:
Step 1: Visit Twitch.tv and sign in to your account or create a new one if needed.
Step 2: Click on your profile picture in the upper-right corner of the page and select "Wallet".
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Step 3: In the "Gift Card Balance" section, select "Redeem Gift Card".
Step 4: Enter your Twitch gift card code then click on "Redeem".