Choosing the correct size

I’m always inbetween sizes given in a pattern - is it better to go smaller or larger, or is there a method for resizing to fit your actual measurements. Usually I’ve gone smaller with yarn that I can block a bit larger but I’m getting ready to use yarn that has no stretch to it.
Specifically, the cardigan pattern has Small - 35 1/2 bust, Medium - 39.
I’m a 36 bust but like my clothes on the looser side, maybe just not several inches too loose. Thanks for your input

Welcome to KH. Do you need to adjust the whole pattern or just want the bust to have more room?

Mostly the bust, but I’d be fine with a little room overall. Length is okay. I like cardis to fit over other long sleeve garments so not sure if the sleeves will be affected by the sizing difference.

Just bust enlargement can be done with short rows. For adjusting the entire pattern I must leave you to better minds than mine. I’m sure there is help here for you.

It’s a good idea to knit a gauge swatch with your yarn. That’ll help you figure out the size to knit. You may be tighter or looser than the pattern calls for and you can use that to your advantage in this case.