find the skin which you wish to install on your Yahoo Messenger through browsing and then download it.
The downloaded file will be transferred into your Downloads folder in the form of a Zip folder.
Using WinZip, unzip the file
Go to my computer and enter into C drive from the Program Files Folder.
Search for Yahoo folder and then open it, a sub folder by the name of Messenger will be found, double click it and then move into the Skin folder.
In your Skin folder, create a new folder and rename it according to the skin type you have downloaded, for instance if it’s a flower, rename your folder as ‘Flower’. You can rename the file by right clicking the folder and selecting rename form the visible options.
After completing the procedure mentioned above, go back towards the unzipped file and drag and drop each file into the folder that was made earlier; this can be done by resizing both windows and then dragging each file to drop into the new folder.
When all the wp-content/uploads have been dropped into the new folder (Flower folder), sign into your Yahoo Messenger.
After getting logged in, drag your cursor towards Preference and click it.
A window will appear on your screen where you can see the option of Appearances on the left side, click it.
Next to Current Theme an arrow pointing downwards is available, click it. You will see the new skin which you have downloaded recently.
Select the skin and click OK. Your new skin will be on your Yahoo Messenger’s window.