Then choose a pack that will barely carry those items -- a bigger pack is only a temptation to overload yourself.
<laughs>
Vern speaks truth there. If you've got room to carry it, you'll carry it.
My choice of packs for 1-day, 3-day and expedition (8 - 16 day) is based on three decades of backpacking/mountaineering in TN (Smokies), trans-Pecos TX (Big Bend), NM (mainly Sangre de Cristo), AZ (Superstition Wilderness), UT (
canyons), CO (mainly
the Weminuche wilderness), WA and OR (Northern Cascades and
Great Basin desert.)
I began by reading the backpacker's bible:
The Complete Walker by
Colin Fletcher. From Fletcher I learned the
incalculable value of finding a good pack that
fits. In his words, you don't "carry" a good pack but "wear it". A well-designed, properly fitting pack can mean the difference between misery and comfort.
Then, find the "minimum" gear that you need in the lightest version available. Take what you need, but make sure you really need it. The pack will remind you that ounces add up to lbs on those 3-hour uphill stretches dominated by "switchback" (even quicker if it's just "up" with no switchback). Is that tiny espresso maker really necessary?
How many compress bandages do you really need? Full tent or just a strong tarp?)
Fletcher tells stories of carrying a postal scale to the mens dept to buy the lightest underwear.
He wrote that he knew he'd gone too far when he found himself tearing the paper tabs off of tea bags to save weight.
__________
{Added by edit: yes, the linked photos are mine. One trip into the Weminuche for 10 days included a 35 mm camera with small tripod. That pack was 72 lb at the beginning of the trek.}