Put number 1 in the middle of the top row. Put the numbers 2 up to n (= length of the square) each time one cell diagonal up and to the right. Put number n+1 below number n. Put the numbers n+2 up to 2n each time one cell diagonal up and to the right. Put number 2n+1 below number 2n. Etcetera ...
19x19 symmetric magic square
192 | 213 | 234 | 255 | 276 | 297 | 318 | 339 | 360 | 1 | 22 | 43 | 64 | 85 | 106 | 127 | 148 | 169 | 190 |
212 | 233 | 254 | 275 | 296 | 317 | 338 | 359 | 19 | 21 | 42 | 63 | 84 | 105 | 126 | 147 | 168 | 189 | 191 |
232 | 253 | 274 | 295 | 316 | 337 | 358 | 18 | 20 | 41 | 62 | 83 | 104 | 125 | 146 | 167 | 188 | 209 | 211 |
252 | 273 | 294 | 315 | 336 | 357 | 17 | 38 | 40 | 61 | 82 | 103 | 124 | 145 | 166 | 187 | 208 | 210 | 231 |
272 | 293 | 314 | 335 | 356 | 16 | 37 | 39 | 60 | 81 | 102 | 123 | 144 | 165 | 186 | 207 | 228 | 230 | 251 |
292 | 313 | 334 | 355 | 15 | 36 | 57 | 59 | 80 | 101 | 122 | 143 | 164 | 185 | 206 | 227 | 229 | 250 | 271 |
312 | 333 | 354 | 14 | 35 | 56 | 58 | 79 | 100 | 121 | 142 | 163 | 184 | 205 | 226 | 247 | 249 | 270 | 291 |
332 | 353 | 13 | 34 | 55 | 76 | 78 | 99 | 120 | 141 | 162 | 183 | 204 | 225 | 246 | 248 | 269 | 290 | 311 |
352 | 12 | 33 | 54 | 75 | 77 | 98 | 119 | 140 | 161 | 182 | 203 | 224 | 245 | 266 | 268 | 289 | 310 | 331 |
11 | 32 | 53 | 74 | 95 | 97 | 118 | 139 | 160 | 181 | 202 | 223 | 244 | 265 | 267 | 288 | 309 | 330 | 351 |
31 | 52 | 73 | 94 | 96 | 117 | 138 | 159 | 180 | 201 | 222 | 243 | 264 | 285 | 287 | 308 | 329 | 350 | 10 |
51 | 72 | 93 | 114 | 116 | 137 | 158 | 179 | 200 | 221 | 242 | 263 | 284 | 286 | 307 | 328 | 349 | 9 | 30 |
71 | 92 | 113 | 115 | 136 | 157 | 178 | 199 | 220 | 241 | 262 | 283 | 304 | 306 | 327 | 348 | 8 | 29 | 50 |
91 | 112 | 133 | 135 | 156 | 177 | 198 | 219 | 240 | 261 | 282 | 303 | 305 | 326 | 347 | 7 | 28 | 49 | 70 |
111 | 132 | 134 | 155 | 176 | 197 | 218 | 239 | 260 | 281 | 302 | 323 | 325 | 346 | 6 | 27 | 48 | 69 | 90 |
131 | 152 | 154 | 175 | 196 | 217 | 238 | 259 | 280 | 301 | 322 | 324 | 345 | 5 | 26 | 47 | 68 | 89 | 110 |
151 | 153 | 174 | 195 | 216 | 237 | 258 | 279 | 300 | 321 | 342 | 344 | 4 | 25 | 46 | 67 | 88 | 109 | 130 |
171 | 173 | 194 | 215 | 236 | 257 | 278 | 299 | 320 | 341 | 343 | 3 | 24 | 45 | 66 | 87 | 108 | 129 | 150 |
172 | 193 | 214 | 235 | 256 | 277 | 298 | 319 | 340 | 361 | 2 | 23 | 44 | 65 | 86 | 107 | 128 | 149 | 170 |
You can use this method to construct magic squares of odd order from 3x3 to infinite and you get a symmetric (but not pan)magic square.
See 3x3, 5x5, 7x7, 9x9, 11x11, 13x13, 15x15, 17x17, 19x19, 21x21, 23x23, 25x25, 27x27, 29x29 and 31x31