I personally do not like having anything on my back. I take over driving duty for a few art cars so having to constantly put on and take off a pack and potentially loosing it sucks.
It's also annoying and too hot and sweaty to wear all day in the heat.
1. A Camelbak bottle with sippy straw and hands free bottle adapter, which turns your bottle into a hydration reservoir. Clip the bottle to your belt or pick up a cheap belt mounted bottle carrier (Condor makes one with an integrated hose pass through for $15). Don't forget some sort of clip so the straw stays close to your mouth.
2. Essentially the same set up can be had through bluedesert. It's called the smartube. This is slick because it includes a few different bottle adapters. You can turn practically any bottle you have into a hydration system. I own this as well as the camelbak variant. They're only about $12 or $15 from amazon.
The 1 liter smart water bottles are great because its a standard sized bottle, just taller so it will fit into the side pocket of your backpack, or leave it in the bottle cage of you bicycle and route the tube to your mouth.https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcSAvFBV4SYCH5l-fFv_Bmobp2KFIalTwa4_mBt2h9rjWyKbzwZY
I use the camelbak cap or the smartube system with either a 48oz nalgene bottle or a 40oz Hydroflask insulated bottle. They share the same thread for the cap with the Camelbak so you can use either the camelbak cap or the smartube adapter on any of those bottles.
3. A camelbak "unbottle". It's basically a bladder in a small insulated cover. The cover has webbing and loops so you can attach the bladder to anything you like. I like it clipped to my belt when walking or to my tankbag on my motorcycle. I use a retractable key\id badge reel for the bite valve so it always goes back to the same place. Tip, ID badge reels have a short strap with a snap on the end, just the right size to snap over a hydration tube. Use a strong one, the keybaks have ratings in oz or number of keys they will hold up. Not those 5 for a $1 ones from eBay.
4. A lumbar or hip mounted hydration pack. Everyone makes one, camelbak, mountainsmith, smartube, bluedesert, hell, even walmart has some not too crappy ones. Some offer hydration from a bottle, others from a lumbar shaped bladder.