For 1/4" stems I cut bias strips on the 45 degree angle at 1" . Iron these in half and then sew with your 1/4" foot with the folded side against the edge of the foot down the length of the strip.
Once you have done this use bias bar appropriate to the size of your required finished strip size. I have had these bias bars for a while and you can also use zip ties which you can get in quite a small size.
Insert the bias bar into the sewn strip as indicated in the photo trim a small 1/8" from the raw edge so when this is ironed over it will not come out the other side.
Iron this and steam it also remove the bars and give the strip a good steam iron.
You then can place the strip where required on your pattern.