The color contrast is most relevant in the case, if you choose boots or bag very bright shade. For example, if the one and the other is a rich scarlet color, your manner of dress may be considered tasteless or even calling. Therefore, if you choose a red bag, wear black, beige or dark brown boots. In short, combine bright neutral. By the way, it is not recommended to duplicate images, ie if you took a bag with leopard pattern, the boots should be self-colored.
Very interesting is the contrast of textures. Leather and suede, satin and shiny - this is a win-win combination for the case, if you want to choose a bag and shoes one color. Do not forget about the decor: if one item is decorated with crystals, pendants, let him be the only shining spot. Ie a luxurious, richly decorated bag should choose strict boots without ornaments.
If you do not like the color contrasts, and in this case you prefer to choose a handbag and shoes of the same material, use similar shades. For example, you can combine cherry and burgundy, crimson and ruby, etc. Another option - bag and shoes tone on tone in combination with another shade of clothing, it is desirable contrast.
Looks interesting combination of different forms. You can choose simple classic boots and bag the original form: for example, made in the form of a ball, hearts, berries and so on. In contrast, the traditional bag combines perfectly with the original boots. The same applies to the size: you can choose a tiny clutch and high boots with bulky ornaments, or a big bag and shoes strict.