You get to the page layout for a standard salesforce object by going to Setup / Build / Customize / [Field name] / Page Layouts

Note: Page layouts for custom objects are found in Setup / Create / Objects and then you select the custom object hyperlink for the object you want to access.  

In Lightning: you get to page layouts by going to Setup / Object Manager, selecting your object, and you'll find "Page Layouts" in the left column.

There are usually two profiles in HandsOn Connect which have Page Layouts associated with them.  

1) SYSTEM ADMINISTRATOR

2) STAFF

Click on the Right arrow (Lightning) and select Edit to Edit a page layout.

Click on "Page Layout Assignment" to see which page layout is assigned to which profile. You can also reassign page layouts here.

In the example above, the Contact Volunteer Record Type, has the page layout "Copy of HOC 3.1 Contact (custom)" assigned to the System Administrator, and the "HOC 3.1 Contact Layout" assigned to the Staff Profile.  

Click on Edit Assignment to reassign which page layouts are assigned to which profiles.

Clicking on edit for a page layout will open a WYSIWYG edigtor.

1. Click on the hyperlink "Video Tutorial" in the top right to learn how to make edits to the page. This is a good instructional overview. Also see the HELP section to the right of this link for more details.

2. You can select to see a list of available fields, buttons, custom links, visualforce pages, and related lists in the palette tray to the left.

3. Drag any available item from the palette tray to the right, directly into place on the page below.  Remove items by dragging them back up into the tray.

4. The Mini-Page Layout determines the pop-up hover fields that show up when this object is displayed as a lookup in another record type.

5. Use quick find to quickly find the field you're looking for.

6. The undo button lets you undo the last action you took.

In this case of the T-shirt field we added in a previous article  -- if it appeared on this layout we could just drag it from one location to another.

Because this is a managed page layout, you cannot change its name.  However you can enable or disable personal and public tags for the object here.

Use the Quick Find search to quickly find the field or item you are looking for.

Then drag and drop it onto the page layout below.

Mobile & Lightning Actions determine the actions available when using Lightning.

Each field in the layout has an  'x' icon which quickly removes an object from the page layout.

Or you can drag it back into the field tray.

You can make a field READ ONLY for that layout, or a REQUIRED field.

If this is the only layout you're editing you can use SAVE.  But if you want to quickly edit the other page layouts, use Quick Save.

Click SAVE when you have edited all the layouts for this object you wish to change.