If you start your major scale on C#, you will have 7 sharps:
C#,D#,E# (yes, E#!) F#, G# A# and B# (again, yes, B#) and then back to the 'tonic', C#. Isn't it easier to play in "Db" (enharmonicly the same as C#) sinc it has 5 flats, rather than 7 sharps. (Db,Eb,F,Gb,Ab,Bb,C and tonic-Db)
A little rule - scales add to 12: a scale in 7 sharps is the same as the enharmonic scale in 5 flats (7+5=12), a scale of Bb with 2 flats is the same as A# with 10 sharps (which includes the double sharps!). Knowing this rule makes it easy to figure out whether to play in sharps or flats.
All the best!