Want to make mittens with gumdrop stitch

Either you messed up or whoever wrote instructions messed up. You'd have to have 150 stitches to end up with 75. Unfortunately, I think that you lost a few stitches somewhere. This is why I don't knit anymore. :)

I had never heard of m1, but it turns out it stands for make 1. I always knew this as increase 1. The way I was taught was to knit a stitch and then put it back on the left needle, to knit it again. Bernina has a video that shows a different method which I'll be trying because it doesn't add any "bump" like my method did. See https://duckduckgo.com/?q=knitting+m1&atb=v72-5__&ia=videos&iax=videos&iai=E31Il_LeKs4

Hello, Patricia -

Do you mean you do not know how to cast on the number of stitches required for the size of cardigan you wish to knit?

You may find this YouTube video instructive:
https://www.youtube.com/watch?v=RWLtMqP6Uz0

After casting on the required number of stitches, the pattern calls for the garter stitch. That means you will knit every row (use the knit stitch) until you reach the required length for the size you are knitting.

For more questions on the pattern, look at this web page:
https://www.yarnspirations.com/bernat-side-street-cardigan--xs-s/BRK0129-007943V.html
There you can click or tap on the Ask A Question link, and ask your question/s.

Best wishes.

Usually increasing stitches is accomplished by knitting (or purling) twice in the same stitch.

How to Increase and Decrease Knitting Stitches For Dummies

Decreasing is accomplished by knitting (or purling) two stitches together.

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It may be helpful to you to join the knitting community called www.ravelry.com, many knitting patterns are listed and reviewed there by the community members with forums discussing issues found as they've knitted the pattern. Often typos slip in and it takes a competent knitter to make the pattern and spot the error.

You can try some of these sites:

http://www.knittingpatterncentral.com/directory/baby_booties_mittens.php
http://www.allfreeknitting.com/Knitting-for-Babies/Little-Baby-Mittens
http://www.ravelry.com/patterns/library/easy-knit-baby-mittens

You need to join ravelry.com, great knitting community with loads of pattern abbreviations, yarn database etc. you will need to join the group to see but its free.

If you are working on the right side of the work, it looks better to purl the two together.
Conversely, if you are working on the wrong side of the work, it looks better to knit the two together.

First of all try a guage/tension swatch. Cast on 25 stitches, use 5,5 mm needles and knit stocking stitch for 4 ins. This should tell you if the pattern will work with these needles and yarn.
Count your stitches over the 4 ins and see wht you have to the inch. This is your guage oe=r tension then check with your pattern to see what the guage/tension is.
To change a pattern this drastically needs an experienced knitter
If it is the pattern only that you want. then find a pattern for 8 ply and use the stitch count on the original pattern and modify for the new pattern.I wish you luck.