Watch the 12/8 Blues 1 online guitar lesson by Jeff McErlain from Blues Survival Guide: Rhythm Edition
A trick to any slow blues to keep the time together is to count the triplets in your head. We could count just beats 1, 2, 3, and 4, but when the tempo is super slow it is very difficult to not rush or drag. If we count the triplets and time 12/8 it is much easier to keep it together, the triplets also give us the proper pulse that is so important in a slow blues. This technique work for any very slow tempo, we can count it in double-time as not to rush or drag. The same concept holds true for extremely fast tempos but in reverse, count them in half time. It make that tempo feel much more manageable.