Create an Outline (Keyline) Around an Icon Across Layers in Photoshop
You can create a consistent keyline around multiple objects by grouping layers and applying a Stroke to the group. This method stays flexible, updates automatically when you edit smart objects, and supports multiple strokes for highlights.
Step-by-step instructions
Prepare and group your icon layers
Select the relevant layers in the Layers panel
Press Ctrl+G (Windows) / Cmd+G (Mac) to group, and name it “Icon”
Optional: Duplicate a layer (Ctrl+J / Cmd+J), then Edit → Free Transform (Ctrl+T / Cmd+T) → right-click → Flip Horizontal to mirror it
Add an outline stroke to the group
Double-click to the right of the group name to open Layer Style
Select Stroke
Set Position: Outside, choose a dark gray Color, and raise Size until the keyline is as thick as needed
Click OK
Edit smart objects and auto-update
Double-click a Smart Object thumbnail to open it (Illustrator or PSB)
Make your changes, then File → Save
Return to Photoshop to see the grouped outline update automatically
Add a highlight stroke (second instance)
Reopen the group’s Layer Style
Click the + icon next to Stroke to add another Stroke
Set a light gray Color and a smaller Size (e.g., 3–4 px), Position: Outside
Optional: Use Gradient or Pattern for stylistic highlights → OK
Transform the grouped icon as one
Select the group and press Ctrl+T / Cmd+T to scale/rotate/move
The outline stays consistent across all grouped layers
