First, the basic concepts of the multivector functions, vector differential and vector derivative in geometric algebra are introduced. Second, we define a, generalized real Fourier transform on Clifford multivector-valued functions (f : R-n -> Cl-n,Cl-0, n = 2,3 (mod 4)). Third, we show a set of important properties of the Clifford Fourier transform on Cl-n,Cl-0, n = 2,3 (mod 4) such as differentiation properties, and the Plancherel theorem, independent of special commutation properties. Fourth, we develop and utilize commutation properties for giving explicit formulas for fx(m), f del(m) and for the Clifford convolution. Finally, we apply Clifford Fourier transform properties for proving an uncertainty principle for Cl-n,Cl-0, n = 2,3 (mod 4) multivector functions.