I am learning as I go along and so far I use steel or brass pins where there is absolute minimal contact with the base but also,like Silicon Dioxide,I use the sprue the model is attached to...slightly different from Silicon Dioxide in that I cut a chunk of sprue from the runner with the leg attached...then I shave down the piece of sprue that is still attached to the foot until it becomes a spike that I can super glue into Green Stuff or modelling clay or whatever I am making the base from.