Create Smart Objects

Do any of the following:

Choose File > Open As Smart Object, select a file, and click Open.
Choose File > Place to import files as Smart Objects into an open Photoshop document.
Although you can place JPEG files, it's better to place PSD, TIFF, or PSB files because you can add layers, modify pixels, and resave the file without loss. (Saving a modified JPEG file requires you to flatten new layers and recompress the image, causing image quality degradation).
Choose Layer > Smart Object > Convert to Smart Object to convert a selected layer into a Smart Object.
In Bridge, choose File > Place > In Photoshop to import a file as a Smart Object into an open Photoshop document.

An easy way to work with camera raw files is to open them as Smart Objects. You can double-click the Smart Object layer containing the raw file at any time to adjust the Camera Raw settings.
Select one or more layers and choose Layer > Smart Objects > Convert To Smart Object. The layers are bundled into one Smart Object. Clipping masks aren’t retained when you group layers into a Smart Object.
Drag PDF or Adobe Illustrator layers or objects into a Photoshop document.
Paste artwork from Illustrator into a Photoshop document, and choose Smart Object in the Paste dialog box. For the greatest flexibility, enable both PDF and AICB (No Transparency Support) in the File Handling section of the Preferences dialog box in Adobe Illustrator.