You can share your YouTube thumbnails or channel banners directly from the PicMonkey Editor to YouTube. To do this you must:
1. Have a verified YouTube account. If you do not, this feature will not work for you. Learn more: Verify your YouTube account (via Google support)
2. Connect to your YouTube account from PicMonkey. You will be prompted to do this when you select the YouTube option from the Share drop-down menu.
How to share to YouTube from PicMonkey
Create a YouTube thumbnail or a channel banner in PicMonkey.
Be sure that your file meets the image requirements below.
Share your finished design directly to YouTube by clicking Share, then selecting YouTube.
Connect to your (verified) YouTube account from PicMonkey.
For banners, If you have more than one channel, select the channel you want to use your new banner for. Click Share.
For thumbnails, select the video you want to use it for. (Note: if you are replacing an existing thumbnail on a video, it'll be deleted from YouTube). Click Share.
Your image(s) are now in YouTube.
Image Requirements:
YouTube Thumbnail:
Have a resolution of 1280x720 (with minimum width of 640 pixels).
Be uploaded in image formats such as JPG, GIF, or PNG.
Remain under the 2MB limit.
Try to use a 16:9 aspect ratio as it's the most used in YouTube players and previews.
Image size and resolution best practices: https://support.google.com/youtube/answer/72431
YouTube Channel Banner:
Best practice: 2560 x 1440 px
Minimum requirement: 16:9 aspect ratio AND 2048 x 1152 px
Image size and resolution best practices: https://support.google.com/youtube/answer/2972003