I use whatever I have on hand that is the correct color. I know, some will disagree, but my bank account is what controls my choices. I may have to adjust my upper tension for some threads. My fav setting is about 1 1/2 on my Juki 98Q. I also pay a lot of attention to the needle size and make sure it is correct. Also, for transparent thread on my Baby Lock Ellegante, I taped a safety pin to the end, just above the wheel, put the thread on a stand behind the machine and thread through the safety pin and then the machine. Works great.