How to space increases and decreases evenly

For most of my own improvised patterns, I don't write out a complete set of pattern instructions.  They're mostly lists of stitch numbers for each round like "6, 12, 18...".  It can be a little troublesome to figure out how to evenly space my increases and decreases from just numbers so I developed a little way to help myself figure it out quickly and get on with the fun part of crochet.

For example, my 10 row sphere has some funny numbers that don't work out so evenly:

For increasing:

1. Subtract the number of stitches in the smaller row (5) from the larger row (9): 9-5=4
• So you will work 4 increases over the 5 stitches from the previous row.
2. Subtract the number of increases (4) from the previous round number (5): 5-4=1
• 4 stitches will be worked as increases and 1 will be worked even
3. Figure out where to place increases and even stitches:
• Divide the number of even stitches (1) by number of increases (4): 1/4=0.25 so in this example, you can see that there are not enough even stitches to put between all the increases.
• Sometimes, like in this example, you'll need to eyeball it and with only a few stitches, it shouldn't be a problem.  If you have 5 stitches to work in and 4 will be increases and 1 worked even, I would put the sc in the middle of the increases, so: Inc, Inc, Sc, Inc, Inc
• For larger numbers, for example, for working round 5, the previous round has 15 stitches and round 5 has 16.  You'll need to work 1 increase (16-15=1) and 14 even stitches (15-1=14).  In this case, you'd want to work 7 Sc, Inc, 7 Sc instead of 14 sc, inc.
• In cases where you have 2 increases to work, you'll want to space them evenly around the circle, keeping in mind where your join is.  For example, for round 4, you have 2 increases to work over 13 stitches (11 even and 2 increases).  You could just work 5 Sc, Inc, 6 Sc, Inc, but to keep it spaced evenly around the join, it would be better to work 3 Sc, Inc, 5 Sc, Inc, 3 Sc.  The number works out correctly in both methods, but the second gives you a more even shape, and working each round with that in mind will keep your whole shape more even.  It helps me a lot to visualize what I'm doing:

Increase with the join in mind, like on the right side.

• So for each round, you'll want to divide the stitches worked even by the number of increases and then take one section and break it in half for either side of the join.  They won't always work out evenly, so it's ok to put 3 on one side and 4 on the other, for example.  One more example: for an 11 row sphere, row 5 is 18 stitches worked over 16 stitches from round 4.  18-16= 2 increases, and 16-2 = 14 even stitches over 16 from the previous row.  Even stitches (14) divided by increases (2): 14/2=7.  So you'll have two sections of 7 sc and 2 increases.  Divide one of the sections of 7 in half (3 sc and 4sc) and put them on either side of the join.  So you could wind up with either 3 sc, inc, 7 sc, inc, 4 sc or 4 sc, inc, 7 sc, inc, 3 sc.  If you are making a sphere, when you come to the sister decrease round, do the opposite way.  You could also make it so every round is a mirror by slightly changing the totals.  For example instead of splitting 3 and 4 around the join, you could do 3 on both side and 8 in the middle or 4 on both sides and 6 in the middle.  If you're using the seam side of the ball as a head for example, this might give you the best result so that the side with the seam is the back.

For decreasing, it's worked much the same way.  Keep in mind that if you are making a ball, you only have to figure out the increase rounds and then just copy them to the appropriate decrease round because the number will be the same, you'll just be decreasing in stead of increasing.

1. Subtract the current smaller round's stitches from the larger previous round's stitches to find the number of decreases.  
• For row 8 with 13 stitches: 15-13 = 2 decreases
2. Multiply the number of decreases by 2 and subtract that from the number of stitches from the previous round to find the number of stitches worked even.
• 2*2=4, 15-4= 11 stitches worked even
3. Then divide the even stitches by the decreases and split one section around the join.
• 11/2=5.5 (5 and 6, split the even one)  So Sc 3, dec, Sc 5, dec, Sc 3

Once you have the method down, you can do rows with large numbers without much of a problem.

Example: in a 40 row ball, row # 13 will have 56 stitches worked in the previous round's 53 stitches.  There will be 3 increases and 50 stitches worked even.  50/3 is 16.67 so you'll have the join, about half of 16, inc, about 16, inc, about 16, inc and about half of 16 again.  When you put in actual numbers and adjust it a little, it works out to: Sc 8, inc, sc 17, inc, sc 17, inc, sc 8.

A little calculator to help out: https://docs.google.com/spreadsheets/d/1y_eqsUS7KwJDe2CrijShjhv7yRAdE193_PmSBDBHYtk/edit?usp=sharing