Most of time, the plot generated using Mathematica is not a good one for projectors because the font size and ticks size are small. BaseStyle is a good solution to this problem. Here is an example from Wolfram Language

Plot[Sin[x]^2, {x, 0, 2 Pi}, PlotLabel -> Sin[x]^2, LabelStyle -> Black, FrameTicksStyle -> Larger, BaseStyle -> \
{FontWeight -> "Bold", FontSize -> 18}]


As shown in the example, LabelStyle->Black and FrameTicksStyle->Larger are also very useful when producing slides for projectors.

More on Wolfram Language: Formats for Text in Graphics.