You can install a GiveForm on a Squarespace website either directly on a page or in a popup (modal).
Select your desired form.
At the top right of your Form Editor, click Embed My GiveForm.
Next, copy the embed code based on whether you want to embed your form directly on a webpage or in a popup.
In Squarespace's website editor, open the page where you'd like to embed your GiveForm.
Click an insert point where you want the form to go.
Next, click on </> Code option.
Paste the embed code from Step 1 into the box, then click apply.
You're done! Now wait for those donations to come rolling in.