Place a Legend inside a Plot 

In[1]:=

X styleoptions = Sequence @@ {BaseStyle -> Gray, Filling -> Axis, Frame -> True, FillingStyle -> Array[# -> Opacity[0.3, {Hue[0.58, 1, 1], Hue[0.12, 1, 1], Hue[0, 1, 1], Hue[0.5, 1, .7], Hue[0.67, .5, 1], Hue[0.17, 1, .8], Hue[0.9, 1, .8], Hue[0.11, .7, .9], Hue[0.61, 1, 1], Hue[0.08, 1, 1]}[[#]]] &, 10], LabelStyle -> {FontFamily -> "Helvetica", 14, GrayLevel[0.3]}, PlotStyle -> (Directive[AbsoluteThickness[4], #] & /@ {Hue[0.58, 1, 1], Hue[0.12, 1, 1], Hue[0, 1, 1], Hue[0.5, 1, .7], Hue[0.67, .5, 1], Hue[0.17, 1, .8], Hue[0.9, 1, .8], Hue[0.11, .7, .9], Hue[0.61, 1, 1], Hue[0.08, 1, 1]})};

Use scaled positions to put a legend inside a plot.

In[2]:=

X Plot[Evaluate[Table[BesselJ[n, x], {n, 1, 5, 1}]], {x, -3, 3}, ImageSize -> 400, PlotLegends -> Placed[LineLegend[Range[1, 5], LabelStyle -> {GrayLevel[0.3], Bold, 18}, LegendLabel -> BesselJ[n, x], LegendLayout -> {"Row", 2}], {0.75, 0.25}], Evaluate@styleoptions]

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