Some people are great at handling their inventory but the rest of us need larger bags. These bags come in 3 variants, regular oiled and invisibly.
Requirements: These bags are account bound so you need 500 in tailoring, leather working or armorcrafting. The only other way to get them is that the 24 bag drop rarely in the final chest at "Breaking the bank" (see Spool of Deldrimor Thread). I havn't got one there myself but I only got the final chest 5 times or so. You don't need PoF to craft them but if you don't you need to buy all mats from the AH so it helps if you do.
There is a recipe for each of the 24 bag (can be bought or looted in "Breaking the bank, I gotten several in the last chest but 1 in each chest 2 & 3. The 28 and 32 are done through discovery. Don't be upset if you don't loot them, they are cheap to buy.The 24 bag:
2 20 slots bags of the model you want to make.
4 Spool of Deldrimor Thread. These can be bought or you find them in chests. Go into the dwarven ruins just south of Derelict Ruins waypoint and run past the mastery insight/vista until you get to the room with a bunch of priory NPCs. From there, look for another room with a bunch of broken cart tracks. Once you are in that room, you want to look for a small opening to your right that will lead you to the room for the curious bowl. Put in a gold piece and you get into a room with 2 chests in, pick one at random and either get a chest and pass to the next room or get teleported back (50/50). The first box will give you a single thread, the next 2 1-2 and the final chests a bunch + a chance at a 24 bag.
1 Supreme Rune of Holding. Can be bought for around 12 golds or won in the casino playing the sandstorm game. Unless you are lucky it is probably cheaper to buy it but also less fun.
1 Pulsing Brandspark (leatherr bag, looted from unidentified rare gear, crafted or bought) , 10 Sliver of Twitching Forgemetal (metal, looted or bought) or 100 Congealed Putrescence (cloth, looted or bought).
That will give you 1 24 slot bag and while it isn't cheap I think it is worth it, I made 3 for my main myself.The 28 bag
needs a single 24 bag, 5 supreme runes and the rest same as the 24 bag. I would not get it unless I already had full of 24 slots and still need more space, unless you are really lucky those runes will cost you 60 gold.The 32 bag
needs a 28 bag, 12 runes and the rest same again.
I think that is about it, good luck and fair journeys.