help in microstrip butterworth low pass filter

hi everybody h r u?
i am new to this forum and also i am new to microwave field ,will my project is on microstrip butterworth low pass filter and i am using CST microwave studio(EM simulation diagram) so i don't how to put two and more microstrips together to form the filter,whether each two microstrips are added together from the center or from the end of one of them to the others head or what?
and also note that i am not using the stepped impendence technique, i am using the normal method
thanks in advance