Downsizing a pattern

I want to make the LIGHT AND LACY WRAP A LEISURE ARTS PATTER. IT CALL FOR A CAST ON OF 99. .I ACTUALLY WANT TO MAKE IT SCARF SIZE. CAN ANYONE HELP ME? IN TERMS OF MAKING IT SCARF SIZEm. Thanks a bunch

It depends. If there’s a stitch pattern that’s made up of x number of repeated stitches, (6, 8 11…) then you have to have a number that works with the pattern repeat. Next is how many sts/inch you get with the yarn and needles you have, then multiply that times the width you want it - 5 or 7 or 9 inches or whatever.

we can help you of course. But I personally would need a little more information.
Is that pattern available online? I only found some crochet instructions but maybe I did not spend enough time googleing.

Most patterns can be made smaller while keeping the stitch pattern going on. If the pattern has repeats you can do it like suzee said. Just some patterns do not have that easy structure.

Between a wrap and a scarf there is not fitting issues or changes of shape, so I am confident it is possible.

depending on how much smaller you want it, you could also maybe use much thinner yarn and needles and therefore make the thing to 99 stitches and the entire instruction but come out smaller.