how to get a closer shave- a safety razor or cartridge razor

[c=BF0080][i]i have a cartridge razor and safety razor both gillette, ive never used a safety razor before, its still unused in the box it came in, i regularly use a gillette labs cartride razor, but sometimes the shaves are shit and i can't get a closeshave so my skins like a babies bum? should i start learning to use a safety razor instead?

any shaving tips? plus, what should i apply after a shave first, aftershave or post aftershave balm?[/i][/c]