This article explains how to create and use Live Stickers on iPhones and iPads.
In the Photos app, find the photo you want to use to create the sticker.
Tap and hold the part of the photo that will become the sticker.

Photos will detect your selection.
Let go when the menu pops up.
Live Stickers can include the small animations that come withLive Photos.

To turn off the animation and make the sticker static, tapLivein the top left and then tapOff.
The item extracted from the photo will appear in the Stickers menu.
If you don’t like it, tapDelete.

Alternatively, you could tweak the look of the sticker by tappingAdd Effect.
Tap each effect to see it applied to the sticker.
When the sticker looks the way you want, tapDone.

To view all Stickers, tap the icon next to Recent Stickers.
Make your pick and skip 9.
To create a new sticker, tap+.

Find and tap the photo you want to create a sticker from.
The app will auto-detect key elements of the photo and outline them for use as a sticker.
To change the style of the sticker, tapAdd Effectand tap the options.
to change the style of the sticker.
TapDeleteto trash the sticker.
Happy with the sticker?
Tap the sticker to add it to the message field.
Add text if you want.
Tap the up arrow to send the sticker.
launch the image, and then go toEdit>Markup>+(plus sign)Add Sticker.
Then, drag a sticker where you want it on the photo.
Sticker packs for your iPhone and iPad are available in the App Store.
Search for “stickers” to find new ones.
Once you install, they should appear in the app tray in Messages.