Note that the "squares" on the diagram must look square, ie one unit of length horizontally must equal one unit of length vertically.
The data used to create this sundial are listed below, if you want to make your own large "walk-on" sundial. The columns are:
Nelspruit Time Xtime Ytime date Xan Yan Teqn XTeqn 05h00 2.183 -0.235 Jan01 -0.036 0.865 -15.00 -0.164 05h30 2.235 -0.110 Jan15 -0.091 0.790 -10.00 -0.109 06h00 2.250 0.016 Feb01 -0.134 0.634 -5.00 -0.055 06h30 2.225 0.142 Feb15 -0.139 0.465 0.00 0.000 07h00 2.163 0.266 Mar01 -0.122 0.279 5.00 0.055 07h30 2.064 0.385 Mar15 -0.089 0.085 10.00 0.109 08h00 1.929 0.498 Apr01 -0.039 -0.153 15.00 0.164 08h30 1.762 0.602 Apr15 -0.001 -0.341 09h00 1.564 0.696 May01 0.029 -0.541 09h30 1.339 0.777 May15 0.036 -0.688 10h00 1.092 0.846 Jun01 0.023 -0.819 10h30 0.826 0.900 Jun15 -0.004 -0.874 11h00 0.546 0.939 Jul01 -0.035 -0.869 11h30 0.256 0.961 Jul15 -0.058 -0.805 12h00 -0.038 0.967 Aug01 -0.060 -0.667 12h30 -0.331 0.957 Aug15 -0.045 -0.504 13h00 -0.619 0.930 Sep01 0.000 -0.304 13h30 -0.896 0.887 Sep15 0.046 -0.117 14h00 -1.158 0.830 Oct01 0.101 0.105 14h30 -1.400 0.758 Oct15 0.139 0.295 15h00 -1.618 0.672 Nov01 0.161 0.515 15h30 -1.808 0.576 Nov15 0.152 0.672 16h00 -1.967 0.470 Dec01 0.107 0.809 16h30 -2.093 0.355 Dec15 0.050 0.872 17h00 -2.183 0.235 -0.036 0.865 17h30 -2.235 0.110 18h00 -2.250 -0.016 18h30 -2.225 -0.142 19h00 -2.163 -0.266