The best tip when using an eyeliner is to apply a thin layer/line rather than a thick one. The thicker your eye liner the smaller your eyes will look. Apply it close to your lash line with a thin layer. You can trace a line with an eye pencil first to make it easier. Try using a brown pencil all over your eye lid, smudge it to give yourself a smokey look. Then use a liquid eye liner and apply it very close to your upper lash line. I'd suggest using a brown eye pencil for your lower lash line and then smuding it to make your eyes look extra big.
White eye liners also workk. You can use them in any way you want. Apply it on the corners of your eye. Your eyes will look big and fresh. I'll take this one step farther and give you some more tips in making your eyes look big in terms of eyes shades. In working with eye shadows, use a lighter eye shade on the eyelids rather than a dark eye shadow color. Brush a soft creamy color along the eyelid and up and out to a diminishing effect. Keep the darker color below the crease. Don't put the eyeliner all around the eye, it closes in the eye and makes it look smaller. Keep a space between the liners. Try some white eyeliner in the top on the eyelid very close to the eyelash line after a darker shade has been put on. It might be just what the eye needs to look bigger. Put mascara on your eye lashes to make your eyes look bigger. For a more natural look, you can just curl your eye lashes and just highlight the tips of your lashes, in a back and forth motion, with a brown mascara.
Depending on your eye color, you should check this site out:
link This video will defintly help you out:
link As for whether guys like big eyes? or notice them? I can assure you they do. I am no guy but from what I have heard from this site and from personal experiences, most guys are attracted to great looking eyes and of course they notice them.
Hopefully this helped.
Goodluck.