The tips and tricks here are oriented to BYOD (bring your down data) mapping and OpenStreetMap obliquely. Presentation cartography and basic inventory mapping is the focus here. Spatial analytics is touched upon briefly but is not the main focus. This site makes assumptions that OpenSource GIS mostly means: PostGIS as a spatial data store and Mapnik as a rendering engine, a Mappy CSS styling language like Cascadenik or Carto to setup the layers and their appearance. Interactivity is briefly touched on. Actually embedding the resulting tile assets is briefly touched on. Web mapping = API + tiles - Slippy maps on the web have two parts: images tiles that make up the map, and an API framework that stitches tiles together and handles interactive panning and zooming. When tiles aren't enough - Use your web map stylesheet to render larger raster images and export to PDF, EPS, and SVG. Rendering map tiles - Once you're done designing your map, you'll need to render 10s of thousands of tiny image files, hundreds and thousands of megabytes in size. Hosting Tiles - Publish your tiles so others can see them. Amazon S3, EC2, CloudFront, your own server, MapBox.com, etc. Is your map effective? - Take a critical look at your work, evaluate it with a consistent rubric, and ask, 'Is my map great?' Map scales/zooms, coordinate systems - Web maps have 20 preset scales, learn these “zoom” levels and their natural scale equivelents. Also more general map projections. D3.js - A robust data visualization library with built in geography support. Bostock has a great map tutorial, too. QGIS - The open source alternative to ArcMap, but not as industrial strength. It's a GUI for composing maps and doing simple analysis. PostGIS - Store your geography in a spatial database (kinda the open source version of an Esri GeoDB). Faster than raw SHP files when speed matters. Storage default for OSM data. OGR, GDAL - Reproject, sort, filter and otherwise modify Shapefiles and other vector map data formats. GDAL for raster. These are amazingly powerful. TileMill - Desktop 'web' app with an easy installer, powered by Mapnik and Carto. From Development Seed / MapBox. Shapely - Python library for geometric objects, predicates, and operations without requiring PostGIS. Kartograph - Kartograph is a new framework for building interactive vector map applications without Google Maps or any other mapping service. It was created with the needs of designers and data journalists in mind. Tons of map projections, gracefully degrades to IE7. Great for thematic maps that are smaller scale than 1:250,000. Shaded relief - set of utilities for processing DEM (digital elevation models, digital terrain models) and shading that to indicate the shape of mountains and other relief features. Land cover - set of utilities for processing classified TIF images and colorizing techniques to indicate type (or presence) of vegetation and land use. Source.