There is no set way of making a heart emoticon. It totally depends upon the messaging software which you are using.
For instance, if the messaging software is something like facebook, or MSN, you can always opt for symbolizing the heart emoticon.
On the other hand, there is also an option of selecting the heart from the emoticons’ tab found close to the sent box which will eventually help you send a message.
In order to symbolise the emoticon, you first need to find the '<' on your keyboard. Press shift and then press ',' to make the '<' sign. Then add a '3' to it in order to complete the heart symbol. The overall look of the heart symbol will be: '<3'
On the other hand, a few softwares even offer you to select a heart emoticon from under their emoticons’ tab. Start off by exploring that tab. Once you take you click on it, you will see several options to make and send different smileys which it offers. Keep searching for the heart emoticon. It is mostly situated close to other love-related emoticons such as a flower.
A few messaging softwares do not let you scroll through the list of emoticons they are offering. If they do not automatically make a heart with the help of step two, then you should opt for another way.
Make a “(“symbol and then type down “l” without any spaces. Close the bracket by adding another “)” at the end. The eventual shape of this would be (l). This will help you make a heart emoticon through the software. Eventually you will not be sending a (l), but a heart which the software will decode itself.