Sweetness comes from many sources, but basically unfermented sugars, or less hops, or a different yeast. One way is to use specialty grains that provide complex sugars that the yeast cannot digest. Another way is to use a different yeast ( like ale yeast) that creates a sweeter profile. Or add lots of sugar, more than the yeast can ferment. Or just use less hops.
It also depends on the combination of ingredients, so for a more definite answer, post your recipe and let the forum look at it.