CrouchingBruin on "[Theme: Twenty Thirteen] Avoiding footer and sidebar on the home page"

You can add the following CSS to hide the sidebar and the footer from just the home page:

body.home #tertiary, body.home footer {
	display: none;
}

You can add the CSS either by creating a child theme or by using JetPack's Custom CSS field (from the JetPack options screen scroll down until you find Custom CSS and click the Configure button).

You'll probably want to increase the width of your main content area, to use the space that's left by the sidebar. You can add this CSS as well:

body.home .entry-content {
	max-width: none;
	padding-right: 60px;
}

Again, this will only affect the content on your home page.