Relocate menu from left-vertical to top-horizontal

I am completely new to wordpress and I use the Awesome Theme. I have deleted the default pages and made new ones, but I can’t see the menu now: not even on the default left menu of the theme. I have been reading info pages on menus for a few hours, but I just don’t get it.

Can somebody tell me how to:

a) get my menu to display
b) get my menu to display on the top, horizontally, instead of on the left, vertically?

Pages I have been reading, clearly not for newbies:
http://codex.wordpress.org/Navigation_Menus
http://codex.wordpress.org/Function_Reference/wp_nav_menu
http://codex.wordpress.org/Function_Reference/has_nav_menu
http://generatewp.com/nav-menus/?clone=header-footer-menus

—————————–

CURRENT MENU CODE CUT FROM THEME

## Menus
————————————————————–*/
.main-navigation {
clear: both;
display: block;
float: left;
width: 100%;
}

.main-navigation ul {
display: none;
list-style: none;
margin: 0;
padding-left: 0;
}

.main-navigation li {
float: left;
position: relative;
}

.main-navigation a {
display: block;
text-decoration: none;
}

.main-navigation ul ul {
box-shadow: 0 3px 3px rgba(0, 0, 0, 0.2);
float: left;
position: absolute;
top: 1.5em;
left: -999em;
z-index: 99999;
}

.main-navigation ul ul ul {
left: -999em;
top: 0;
}

.main-navigation ul ul a {
width: 200px;
}

.main-navigation ul ul li {

}

.main-navigation li:hover > a,
.main-navigation li.focus > a {
}

.main-navigation ul ul :hover > a,
.main-navigation ul ul .focus > a {
}

.main-navigation ul ul a:hover,
.main-navigation ul ul a.focus {
}

.main-navigation ul li:hover > ul,
.main-navigation ul li.focus > ul {
left: auto;
}

.main-navigation ul ul li:hover > ul,
.main-navigation ul ul li.focus > ul {
left: 100%;
}

.main-navigation .current_page_item > a,
.main-navigation .current-menu-item > a,
.main-navigation .current_page_ancestor > a {
}

/* Small menu. */
.menu-toggle,
.main-navigation.toggled ul {
display: block;
}

@media screen and (min-width: 37.5em) {
.menu-toggle {
display: none;
}
.main-navigation ul {
display: block;
}
}

.site-main .comment-navigation,
.site-main .posts-navigation,
.site-main .post-navigation {
margin: 0 0 1.5em;
overflow: hidden;
}

.comment-navigation .nav-previous,
.posts-navigation .nav-previous,
.post-navigation .nav-previous {
float: left;
width: 50%;
}

.comment-navigation .nav-next,
.posts-navigation .nav-next,
.post-navigation .nav-next {
float: right;
text-align: right;
width: 50%;
}

Thanks