Before beginning, make sure that the image is uploaded to WebEdit.
Reference: How to Import Images into WebEdit.
Editing the page
Locate the page you wish to edit. Click either the Edit tab or the yellow pencil icon next to the content area.
Note: Clicking a pencil icon will will open the in-context editing tool. If you prefer, click the Edit tab. (Screen captures below show the steps using in-context editing.)

Select the image location
Click in the Content area at the desired location for the image. If the image will be on a line by itself, insert a blank line in the Content area.
Click the insert image icon in the toolbar.
Choose an image
The insert image window offers two tabs – one for internal images and one for external. Stay in the internal tab and click the Choose File icon.
A list of the most recently uploaded or accessed images will drop down. If the image is on this list, click to select. If not, click Browse at the top of the list.
If the Browse button is selected, navigate to the folder containing your image in left asset tree, select the image file, and click the Confirm button.
Alternate Text
The image path will appear in the insert image window. In the Alternate Text field, enter a short description of the image (example: squid drawing). Click the Insert button.
Save as draft
Click the Update button on the content window to save a draft.
Note: This step only applies if you are using in-context editing. If editing via the Edit tab, click the Submit button to save.
Review and save
Look at the page. If everything looks good, click the Submit Draft button.
Note: This step only applies if you are using in-context editing.
Spell check
A spell check may appear. You can either modify specific words, or leave them set to "ignore" and Submit
Publish changes
When the updates are ready to go live, publish the page. The image you placed on the page will automatically publish when the page is published.