Its not important.... its freaking
important.
Guys, regardless of how weird you feel when you have to hold your
gf's hands for more than five minutes - to a woman's point of view:
generally, gestures that show and display your affection, is
close-to-essential of 'upkeeping' your relationship. 
A definitely 'must-have'
I) Hugs, cuddlings, etc
II) Holding hands, across waist, etc
III) Lots of muackz and kisses on lips, nose, neck, etc.
The power of body language in relationship generally speaks louder
than words. 
P.S: Your partner is a very special person and in return for being
so special in your life - affection is exchanged. Afterall, if your
affection is not generous to her/him, then who do you wish to
shower your affection to? 
Cheers