Mark up email attachments in Mail on Mac
When you’re writing a message and add an image or PDF document, you can use Markup to write or draw on the attachment, rotate or crop it, or add shapes or a signature to it.
Tip: You can use the Markup tools to add your own drawing directly to your message. Control-click anywhere in the body of your message, then choose Insert Drawing.
Go to the Mail app
on your Mac. Move the pointer over an image or PDF you added to your message.
Click
that appears in the upper-right corner of the attachment, then choose Markup.If the pop-up menu isn’t shown, you may need to enable Markup. Choose Apple menu
in the sidebar (you may need to scroll down). Click Login Items & Extensions, go to Extensions, then click By Category. Click 
next to Actions and turn on Markup.Use the tools to mark up the image or PDF.
To adjust the size of your markup items, move the pointer near the edges, then drag the blue handles.
To duplicate any shape, text, or signature, press and hold the Option key while you drag an item; use the yellow guides to align the items.
Tool
Description
Sketch
Sketch a shape using a single stroke.
If your drawing is recognized as a standard shape, it’s replaced by that shape; to use your drawing instead, choose it from the palette that’s shown.
Draw
Draw a shape using a single stroke. Press your finger more firmly on the trackpad to draw with a heavier, darker line.
This tool appears only on Mac computers with a Force Touch trackpad.
Shapes
Click a shape, then drag it where you want. To resize the shape, use the blue handles. If it has green handles, use them to alter the shape.
You can zoom and highlight shapes using these tools:
Highlight
: Drag the highlight where you want. To resize it, use the blue handles.Zoom
Text
Type your text, then drag the text box where you want.
Highlight Selection
Highlight selected text in a PDF.
Sign
If signatures are listed, click one, then drag it where you want. To resize it, use the blue handles.
To create a new signature, see Fill out and sign PDF forms in Preview on Mac.
Shape Style
Change the thickness and type of lines used in a shape, and add a shadow.
Border Color
Change the color of the lines used in a shape.
Fill Color
Change the color that’s used inside a shape.
Text Style
Change the font or the font style and color.
Rotate Left
or Rotate Right 
Click
to rotate the item to the left. Continue clicking to keep rotating.To rotate the item to the right, press and hold the Option key, then click
until you’re done rotating the item.Crop
Hide part of an item. Drag the corner handles until just the area you want to keep is shown within the frame’s border. You can also drag the frame to reposition it. When you’re ready, click Crop.
Image Description
Enter, view, or edit a description of an image. (The tool is highlighted when an image has a description.)
Image descriptions can be read by screen readers and are useful for anyone who has difficulty seeing images online. For example, if you use VoiceOver, the built-in screen reader on Mac, you can press the VoiceOver command VO-Shift-L to hear a description of the image in the VoiceOver cursor.
Form Fill
Type your text in the fields in a PDF form.
Annotate
Annotate the item by sketching or drawing on it using your nearby iPhone
Note: To use your nearby iPhone or iPad to sign or annotate items, it must meet Continuity system requirements. See the Apple Support article System requirements for Continuity features on Apple devices.
When you’re finished, click Done.
You can change or add annotations until you send your message. Once sent, your annotations become part of the image or PDF, and you and your recipients can’t modify them.
