Draw a vertical center line
Sketch a wide base rectangle
Add two slanted legs rising from the base corners
Draw a smaller middle section above the base
Continue narrowing the structure as it rises
Add the first arched opening near the bottom
Add the second arched opening above it
Draw cross-bracing lines inside the legs
Sketch the curved top platform
Add the upper tower section above the platform
Draw the narrow spire at the top
Refine the outline of all four legs
Add horizontal support lines across the tower
Clean up extra sketch lines
Darken the final structure outline
Add small details and lattice lines
Shade lightly for depth