I wear a under armour long sleeve compression "heat gear" shirt in white. I find the UA brand to be lighter then a similar looking champion brand. It helps reflect sunlight and has really helped me out. If this isn't for you consider sunblock.
Also how fast do you travel? You might consider a large Panama hat to keep the sun off. On my bike I go fast enough to always have a breeze.
I also am a huge Hammer fan. They have a really nice beginner endurance package that comes with a variety of their products and some pamphlets on how to fuel for endurance. I really like their fizz tablets and HEED mix.
Of course there are cheaper diy alternatives which are just as good. I just found I had the $$ and their guides really helped me out.
You should be doing a bottle an hour of liquid and electrolyte. You should be consuming only ~ 150 calories per hour and a little protein.