Welcome to OSM! some of the footprints you added are very accurate and I could not have done a better job myself, others however are oversized and are not squared when they should be. 

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the [roofs of buildings](https://wiki.openstreetmap.org/wiki/Key:roof:shape#Roof_shape), but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag.  Take care to make contributions that others can build upon.

After tracing and tagging features which are likely square or round, please remember to square their corners (q), or circularise them (o), because it is almost impossible and time consuming to draw shapes so percisely by hand. Buildings with metal or pitched roofs tend to have square corners; round buildings are identifiable by the distinctive cresent shaped shadow they cast. Unless the building is clearly a different shape then it's best to assume that it should be rounded or its corners should be squared. In the iD Editor, you can right click for access to editing functions. Since roofs tend to overhang walls trace the initial shape slightly smaller to allow a buffer for any change in size that may occur. In JOSM use the [buildingstools plugin](https://wiki.openstreetmap.org/wiki/JOSM/Plugins/BuildingsTools). In ID you must draw the shape accurately enough else shapes will not completely square. This [video about squaring features in ID](https://youtu.be/Xs5wX592E1o) has more information and a demo.

Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/