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One sign that a guy may like you is if he reacts to your posts on social media. He might do more than just "like" your updates. For example, he might comment on your posts or reply to things you upload, or he even may send you direct messages on social platforms.  Look to see if he comments on other people’s posts as well. If he comments frequently, this may just reveal that he is an avid social media user. However, if he rarely “likes” or comments on other posts, this is a sign that he might have feelings for you. After he publicly comments on one of your photos or posts, respond to him. If he is eager to start up a conversation with you this way, it may reveal that he likes you or at the very least enjoys messaging with you.  For example, he may say "That is a great photo! Where are you?" You could respond by saying "I was in Vancouver last week. Such a beautiful city! Have you been?" If a guy you just met starts "liking" or commenting on old photos of you, this is a sign that he is interested. It means that he has spent time looking back through your old photos probably because he wants to know you better or he just enjoys looking at pictures of you! When a guy likes you, he will want to connect with you and follow you on a variety of different social media platforms. For example, he may add you to Facebook and Snapchat, and start following you on Twitter and Instagram. Adding you to a number of social media sites is likely a sign that he wants to look through your posts, photos, and selfies in an attempt to get to know you better.

Summary:
See if he interacts with your posts. Reply to his comments. Notice if he comments on old pictures or posts. Check to see if he has added you on multiple social media platforms.