I have a sweater pattern that calls for size five needles. I want to use size ten, as the person i am knitting this for likes the larger stitches as opposed to the smaller ones. How can i do this and still get the right size?
Make a swatch. Check stitches per inch. Figure out how many stitches per inch around the body (including ease) for your gauge. Find the size in the pattern that uses the closest to that number of stitches around the body and use that pattern. Hopefully you will find a size that has close enough to the right number of stitches.
You would need to figure out your gauge with the yarn and needles you want to use and then convert the pattern to match the new gauge.
Also see if the yarn you're using is the same as in the pattern. If you want to use worsted, that will be fine with size 10s. If the pattern is written for a much thinner yarn, it may be too holey.