Color Brewer: Tool created by Cynthia Brewer that offers advice for using color on maps, specifically with thematic mapping. Lets you export color schemes to various formats.
Mapshaper for generalizing your geospatial data which helps your maps not only look better but load faster. Mapshaper let's you preview how generalized it looks before you export it.
##How to get started contributing to a Humanitarian OpenStreetMap Team task
###Overview
OpenStreetMap (OSM) is an open-source map of the world that anyone can edit. But like any map, it's incomplete.
The Humanitarian OpenStreetMap Team (HOT) helps organize people to improve the OSM map for crisis areas, mostly so aid workers can find their way around and make decisions about undermapped places. The data in these crisis areas is often very poor, or completely non-existent. Therefore any contribution you make at all will be a vast improvement, and could materially help people who are on the ground right now, looking at this data as you edit it, and deciding where to go and who to help.
There are many HOT tasks active at once. As of August 2014, the highest-priority tasks are Gaza and areas affected by the West African Ebola outbreak.