I wash the vulva thoroughly yet gently with water and take care to avoid soap. I don't wash inside my vagina - that is completely unnecessary and a bit akin to washing inside your anus, or washing inside your nostrils, or inside your throat or stomach or urethra (if that were possible!). The vaginal walls are an internal mucosal surface and do not require washing.
The vagina (by which I mean the internal "tunnel", all the outside stuff is vulva) is self balancing, self cleaning and maintains the right pH and number of lactobacilli, essential to preventing overgrowth of anaerobes or thrush. You absolutely shouldn't be putting soap in it or scrubbing it. It doesn't sweat, it simply doesn't produce "dirt" - only discharge which should be clean and is removed every time you change your pants.
Otherwise I keep good vaginal (well more urethral) hygiene by peeing before and after sex, and taking care with anal-vaginal hygiene (always wipe front to back etc).