Here is a comparison table.

SLEEPING PAD

For a sleeping pad, the most important thing is to pad your torso. Use a 20"x40" closed cell foam pad that weighs 3.8 oz. Use more of natural padding in the right places like hips and shoulders. For longer trips, take a Thermarest Ultralight, which weights 18.2 oz. Switching from a full-length Thermarest to an ultralight Thermarest saves 1 pound while switching from a full-length Thermarest to a closed cell foam pad saves 1.5 pounds.

SLEEPING BAG

This is one critical area that may require some investment in new gear. Down-fill bags are lighter than Synthetic-fill bags with the same temperature rating.

Instead of a heavy foam mattress pad, consider a 5 x 2 foot piece built of almost weightless plastic wrapping material. Get the type that has air bubbles about a half-inch thick. Put that on top of a space blanket or similar piece of plastic used as a ground sheet.

If you really want an ultralight sleeping bag then your best bet is a quality goose filled bag. Take a 30 degree bag, which weighs less than a 20 degree bag. Ultralight down bags in the 20-25 degree range weigh 1.3-1.75 pounds. A good ultralight bag should have 750 fill-power down or greater, and have a lightweight water-repellent shell.

Switching to an ultralight down bag saves 2.5 pounds. A 25-30 degree lightweight synthetic bag will weigh about 1 pound more than an ultralight down bag.

Wearing your jacket in your bags will give you extra warmth and avoid the need to carry a heavy sleeping bag.

BACKPACK

This is another critical area for weight reduction.

Once you have drastically reduced the weight of your gear, you do not need a heavy frame pack anymore to carry your gear.

Conventional packs weigh more than 5 kg due to the belief that packs should be high volume, have lots of pockets, zips and straps and constructed from a heavy bombproof fabric. But this belief is not true. It is possible to make a durable pack from high performance fabrics that weigh a lot less.

A minimalist pack (40-50 liters and 20 pounds) will suit a committed ultralite enthusiast on a multi-day trek.

If you can pack really small, maybe you can get it into a large daypack. They tend to be made out of lighter materials, and cost less anyway. They may not have as many features (no external water bottle pocket, etc.).

Most full-featured backpacks weigh 5-8 pounds. Switching to a lightweight frame pack saves 2-3 pounds, or a rucksack saves 4-7 pounds.

For a pack cover, use a plastic trash compactor bag or garbage bag, cut out for the pack straps. Reduce sophisticated suspension systems that weigh a lot.

SHELTER

The ultralite enthusiast's choice is to use a tarp. It weighs only 400 gm and when packed fit into your hand. It will utilize your trekking poles and avoid the need for conventional tent poles.

An alternative is to use a bivy bag/sack. This carries many of the downsides of the tarp at a greater weight and on a warm pleasant summer night does not give the feeling of being part of the environment that a tarp offers.

The final alternative is look for a lightweight double wall tent weighing around 2.5 pounds for 1 person and 3.5 pounds for 2 people. There are several single wall tents on the market that are lightweight, and very tempting. However, be advised that if you choose a single wall tent, condensation is a major issue and the tent must have adequate ventilation.

Conventional 2-person backpacking tents weigh 5-7 pounds. Switching to a lighter tent saves 2-4 pounds while switching to a tarp or a bivy sack saves 4-6 pounds.

…

• Learn to think in terms of ounces and not pounds.
• Write down all your weight calculations and you will see everything more objectively.
• Use a kitchen scale that shows ounces and fractions of ounces to weigh every piece of equipment you have.
• If purchasing new gear, compare the weights of your options by taking your scale to the store.
• When purchasing gear from a catalog or online, insist on knowing the weight before you purchase it.
• Remove parts that are not functional-tags, drawstring from pants with elastic, extra length on draw cords of packs and stuff sacks, extra length on pack straps.
• Take gear that serves multiple uses
• ...