It’s very easy to send email in WordPress

	   $to = $discountEmail;
	   $subject = "Your Subject";
	   $headers = array('Content-Type: text/html; charset=UTF-8');
	   $message = file_get_contents(get_template_directory().'/example.html', true);
	   $attachments = "Attach";
	  wp_mail( $to, $subject, $message, $headers,$attachments

Fun way to create email template that includes responsive design
1. Create a file (example.html) in theme folder and Copy default design as


<!doctype html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Simple Transactional Email</title>
<style>
/* -------------------------------------
GLOBAL RESETS
------------------------------------- */
/*All the styling goes here*/
img {
border: none;
-ms-interpolation-mode: bicubic;
max-width: 100%; 
}
body {
background-color: #f6f6f6;
font-family: sans-serif;
-webkit-font-smoothing: antialiased;
font-size: 14px;
line-height: 1.4;
margin: 0;
padding: 0;
-ms-text-size-adjust: 100%;
-webkit-text-size-adjust: 100%; 
}
table {
border-collapse: separate;
mso-table-lspace: 0pt;
mso-table-rspace: 0pt;
width: 100%; }
table td {
font-family: sans-serif;
font-size: 14px;
vertical-align: top; 
}
/* -------------------------------------
BODY & CONTAINER
------------------------------------- */
.body {
background-color: #f6f6f6;
width: 100%; 
}
/* Set a max-width, and make it display as block so it will automatically stretch to that width, but will also shrink down on a phone or something */
.container {
display: block;
margin: 0 auto !important;
/* makes it centered */
max-width: 580px;
padding: 10px;
width: 580px; 
}
/* This should also be a block element, so that it will fill 100% of the .container */
.content {
box-sizing: border-box;
display: block;
margin: 0 auto;
max-width: 580px;
padding: 10px; 
}
/* -------------------------------------
HEADER, FOOTER, MAIN
------------------------------------- */
.main {
background: #ffffff;
border-radius: 3px;
width: 100%; 
}
.wrapper {
box-sizing: border-box;
padding: 20px; 
}
.content-block {
padding-bottom: 10px;
padding-top: 10px;
}
.footer {
clear: both;
margin-top: 10px;
text-align: center;
width: 100%; 
}
.footer td,
.footer p,
.footer span,
.footer a {
color: #999999;
font-size: 12px;
text-align: center; 
}
/* -------------------------------------
TYPOGRAPHY
------------------------------------- */
h1,
h2,
h3,
h4 {
color: #000000;
font-family: sans-serif;
font-weight: 400;
line-height: 1.4;
margin: 0;
margin-bottom: 30px; 
}
h1 {
font-size: 35px;
font-weight: 300;
text-align: center;
text-transform: capitalize; 
}
p,
ul,
ol {
font-family: sans-serif;
font-size: 14px;
font-weight: normal;
margin: 0;
margin-bottom: 15px; 
}
p li,
ul li,
ol li {
list-style-position: inside;
margin-left: 5px; 
}
a {
color: #3498db;
text-decoration: underline; 
}
/* -------------------------------------
BUTTONS
------------------------------------- */
.btn {
box-sizing: border-box;
width: 100%; }
.btn > tbody > tr > td {
padding-bottom: 15px; }
.btn table {
width: auto; 
}
.btn table td {
background-color: #ffffff;
border-radius: 5px;
text-align: center; 
}
.btn a {
background-color: #ffffff;
border: solid 1px #3498db;
border-radius: 5px;
box-sizing: border-box;
color: #3498db;
cursor: pointer;
display: inline-block;
font-size: 14px;
font-weight: bold;
margin: 0;
padding: 12px 25px;
text-decoration: none;
text-transform: capitalize; 
}
.btn-primary table td {
background-color: #3498db; 
}
.btn-primary a {
background-color: #3498db;
border-color: #3498db;
color: #ffffff; 
}
/* -------------------------------------
OTHER STYLES THAT MIGHT BE USEFUL
------------------------------------- */
.last {
margin-bottom: 0; 
}
.first {
margin-top: 0; 
}
.align-center {
text-align: center; 
}
.align-right {
text-align: right; 
}
.align-left {
text-align: left; 
}
.clear {
clear: both; 
}
.mt0 {
margin-top: 0; 
}
.mb0 {
margin-bottom: 0; 
}
.preheader {
color: transparent;
display: none;
height: 0;
max-height: 0;
max-width: 0;
opacity: 0;
overflow: hidden;
mso-hide: all;
visibility: hidden;
width: 0; 
}
.powered-by a {
text-decoration: none; 
}
hr {
border: 0;
border-bottom: 1px solid #f6f6f6;
margin: 20px 0; 
}
/* -------------------------------------
RESPONSIVE AND MOBILE FRIENDLY STYLES
------------------------------------- */
@media only screen and (max-width: 620px) {
table.body h1 {
font-size: 28px !important;
margin-bottom: 10px !important; 
}
table.body p,
table.body ul,
table.body ol,
table.body td,
table.body span,
table.body a {
font-size: 16px !important; 
}
table.body .wrapper,
table.body .article {
padding: 10px !important; 
}
table.body .content {
padding: 0 !important; 
}
table.body .container {
padding: 0 !important;
width: 100% !important; 
}
table.body .main {
border-left-width: 0 !important;
border-radius: 0 !important;
border-right-width: 0 !important; 
}
table.body .btn table {
width: 100% !important; 
}
table.body .btn a {
width: 100% !important; 
}
table.body .img-responsive {
height: auto !important;
max-width: 100% !important;
width: auto !important; 
}
}
/* -------------------------------------
PRESERVE THESE STYLES IN THE HEAD
------------------------------------- */
@media all {
.ExternalClass {
width: 100%; 
}
.ExternalClass,
.ExternalClass p,
.ExternalClass span,
.ExternalClass font,
.ExternalClass td,
.ExternalClass div {
line-height: 100%; 
}
.apple-link a {
color: inherit !important;
font-family: inherit !important;
font-size: inherit !important;
font-weight: inherit !important;
line-height: inherit !important;
text-decoration: none !important; 
}
#MessageViewBody a {
color: inherit;
text-decoration: none;
font-size: inherit;
font-family: inherit;
font-weight: inherit;
line-height: inherit;
}
.btn-primary table td:hover {
background-color: #34495e !important; 
}
.btn-primary a:hover {
background-color: #34495e !important;
border-color: #34495e !important; 
} 
}
</style>
</head>
<body class="">
<span class="preheader">This is preheader text. Some clients will show this text as a preview.</span>
<table role="presentation" border="0" cellpadding="0" cellspacing="0" class="body">
<tr>
<td>&nbsp;</td>
<td class="container">
<div class="content">
<!-- START CENTERED WHITE CONTAINER -->
<table role="presentation" class="main">
<!-- START MAIN CONTENT AREA -->
<tr>
<td class="wrapper">
<table role="presentation" border="0" cellpadding="0" cellspacing="0">
<tr>
<td>
<p>Hi there,</p>
<p>Sometimes you just want to send a simple HTML email with a simple design and clear call to action. This is it.</p>
<table role="presentation" border="0" cellpadding="0" cellspacing="0" class="btn btn-primary">
<tbody>
<tr>
<td align="left">
<table role="presentation" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td> <a href="http://htmlemail.io" target="_blank">Call To Action</a> </td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
<p>This is a really simple email template. Its sole purpose is to get the recipient to click the button with no distractions.</p>
<p>Good luck! Hope it works.</p>
</td>
</tr>
</table>
</td>
</tr>
<!-- END MAIN CONTENT AREA -->
</table>
<!-- END CENTERED WHITE CONTAINER -->
<!-- START FOOTER -->
<div class="footer">
<table role="presentation" border="0" cellpadding="0" cellspacing="0">
<tr>
<td class="content-block">
<span class="apple-link">Company Inc, 3 Abbey Road, San Francisco CA 94102</span>
<br> Don't like these emails? <a href="http://i.imgur.com/CScmqnj.gif">Unsubscribe</a>.
</td>
</tr>
<tr>
<td class="content-block powered-by">
Powered by <a href="http://htmlemail.io">HTMLemail</a>.
</td>
</tr>
</table>
</div>
<!-- END FOOTER -->
</div>
</td>
<td>&nbsp;</td>
</tr>
</table>
</body>
</html>

2. Edit this template as you want.

By toihid