The method to like a picture of Xiao Long Gao may vary on different platforms or apps.

Here are some general steps and tips:

1. Social media platforms (such as WeChat, Weibo, etc.):

- Open a post with a picture of Xiao Long Gao.

- Find and tap the "Like" button, which is usually in the shape of a hand or a thumb.

- Once tapped, the button may change color or show that the number of likes you have given has increased.

2. Photo sharing or social apps (such as TikTok, Kuaishou, etc.):

- Find a picture with Xiao Long Gao.

- Tap the "heart" icon or similar like button below the picture.

- The icon may light up or increase in number to indicate that you have given it a like.

3. E-commerce platforms (such as Taobao, JD.com, etc.):

- Browse to the pictures of the Xiaolonggao products you are interested in.

- There will usually be a group of icons next to the picture, select the button that looks like "Like" or "Favorite".

- After clicking, the button may change color or state to indicate that you have liked it.

4. Forums or websites:

- Find the post or page showing the picture of Xiaolonggao.

- Look for a link or button with "Like", "Favorite" or similar meanings.

- Click the button and the website may update to show that your like has been recorded.

If you are operating on a platform that requires login, make sure you are logged in to your account, as some systems require users to log in before they can perform interactive operations such as liking.

Please note that the design and interface of different platforms and applications may vary, so the specific icon shapes and operation steps may vary. If you get stuck, you can look up the platform or app's help center or instructions for more detailed guidance.

If the above doesn't solve your problem, please provide more specific information or context so that I can provide more accurate assistance.