My recommendations would be the 6x24 as everyone else has mentioned; a 12.5" square; a 3x6 or similar small size. My other recommendation is to buy all the same brand - whichever brand is right for you. When you start shopping, take the various colors of rulers and lay them over different color/print fabrics that appeal to you. See which color markings work best on the fabric colors/prints that appeal to you most. Then see if that brand has the various sizes you might need. I personally like clear/black lines...find those to be the easiest markings to see on most fabrics. If you can find a wider-than-6" x 24 and also meets the above suggestions, I would go with that.

Many times patterns call for 6.5" borders (or wider) and I love having a wider ruler to measure/cut with than butting 2 rulers together for those wider measurements.

The ones I use on a regular basis: 6.5 x 24, 6 x 12, 6" square and 14" square.

I make lots of quilts and seldom need anything else.

I do have a June Tailor shape cut ruler that I use sometimes and like, but could live without it. Not so the ones above.

If you already have the 6x24 and a good 12.5" square, that's going to pretty much be all you NEED. There are very few things you won't be able to accomplish with those two rulers. Specialty rulers will make certain shapes *easier*, but I'd say you have the basic "needs" covered. So that's pretty cool!

If you're a gadget person and want more: I recommend checking out the June Tailor slot rulers if you're going to be sewing a lot of smaller squares, rectangles & strips. If you're going to sew a lot of triangles, a 60-degree triangle ruler will save you some time. If you do a lot of flying geese, a flying geese ruler is probably going to help out. If you're going to make a double wedding ring quilt, you probably want to check out some of the ruler sets made specifically for that pattern.

They make specialty rulers for just about everything - the question becomes how much do you want to spend, and how many rulers do you want to store that you might only use rarely?

Personally...I love rulers. I have several I have purchased because "some day" I'm going to make a quilt that has [whatever special shape] in it. I've used most of them, but not all of them. (yet!)

My 6-1/2" x 24" ruler BY FAR gets the most use, though. I use it on every single quilt I make, if for nothing else than for as a guide when I'm squaring up. Sometimes that's the ONLY ruler I use for a quilt!

I have a 6 1/2" x 24" that I use to cut my strips and a 4" x 12". I recently just bought a 5" quilt stick love it. Use it to cut 5" charms and they have different sizes of quilt sticks. I have a 12" square to shape up your blocks and few extra square rulers.

I do not buy speciality ruler often. IMHO basic rulers that you need are 6 1/2" x12 or 6 1/2" x 24. and a variety of small square rulers. I bought a 3 pack of square rulers at Joann that has a LARGE 20 x20" ruler. I do not use this often but it is great for cutting wider strips such as 10 1/2'" due it is longer so you get both width and length. You can buy most basic rulers at Joanns with coupons that make them affordable. However joanns does not sell many speciality rulers so those you must buy at LQS.

I find myself using my 8.5" square up ruler most of all and a 2.5" x 12" that I use for cutting jelly rolls strips. You collect rulers as you need them.

Whatever rulers you get, you should get a couple with the angle markings on them. You will need to use angles at some point in time. I have Fiskars square rulers with angles 30, 45, and 60 degree markings. Use coupons when you can. Hexagon rulers are great. I waited to buy specialty rulers til I really wanted to start making a certain block and couldn't figure the angle on one of my rulers. Sometimes it's just easier. Good luck!

Besides the squares and the 6.5x24 I would be sort of lost without my binder buddy ruler. I use it constantly as I always make my own continuous bias binding.

I would not be without my june tailor shape cut, and my 5 x18 ruler, and I also use my 6inch and 9 inch square rulers alot. I would just add specialty rulers as you go, there are so many brands its hard to know which one you will like