I've just got janome 634d serger, how can i make the bottom of a T-shirt ? Thank you so much

If you want the bottom of the T to look like RTW with the double row of stitching, you cannot do this on a serger.

You can achieve the effect by using a twin needle, two spools of thread, bobbin and a straight stitch.

Make sure the double/twin needle will pass through the presser foot and opening in the needle plate below the presser foot.

Practice on a double layer of a scrap of the T shirt material as the tension may need to be slightly looser than the normal setting.

Hi there - as per above, but re your 634D, I have the same serger and was recommended the Janome Overlockers Creative Sewing Guide. I purchased this in Australia, but it guides you through all sorts of things I never ever thought an overlocker could do - i.e. applying elastic; lace application; decorative edging; making spaghetti straps; Picot Hem; lettuce leave edging; blind hemming; **** ; flatlock hemming; flat joining; pintuck; braiding; guides you through using differential feed - attaching sleeves; attaching ribbing; attaching stetch waistbands; if you have the attachments - using elastic foot; blind hem presser foot; piping foot; blind stitch foot; cording foot; taping attachment; elastic gathering attachment; beading attachment; cloth guide. I had over ever used my serger for overlocking seams and this book as allowed me to use the serger to its full potential. If you wanted a copy you could try E-Bay. Many thanks. Bron. :)