You can also do this--

Write out the scale for the key you are in, then write out the scale in the key that you want to transpose to underneath, lets say, D--and just replace the note or chord(major, minor, and interval desiganations stay the same from one key to the next) for the one underneath it. Resist the temptation to make a big block with all the keys, it will be very hard to follow--

C D E F C A B C
D E F# G A B C# D

No counting, no remembering, NO THINKING, therefore, no confusion--