Using markers is a really fun experience! One thing to learn about the markers you have, is if they are water based or alcohol based. Depending on which they are you can do different things with them. I am not as familiar with water based markers but as the name indicates they can be affected by water so they may compliment water coloring. Alcohol based markers, like Copics, are designed to blend smoothly and resist distortion by water. I even spilled a drink on my makered page once and nothing bled. It was amazing!
Anyway, the paper you put the markers on is important. Thick and smooth paper like Bristol allows you to layer more ink on the page before over saturating it. That means you can do more complex styles that look almost painterly. Plus good paper will minimize any marker bleeding.
Markering tips I have learned and feel are useful (for Copics):
1) The more layers of a color, the darker and more rich the color becomes. You can seriously make a gradient with a single marker if you pace your layers right.
2) Markers blend softly if the first coat is still moist. If you wait and let it dry before coloring again you will have crisp lines.
3) To give the affect of volume, use your marker strokes in the direction that makes sense to the object you are coloring. Example: curves for round shapes, or straight lines for flat surfaces.
4) Layering different colors over each other creates new colors. Sorta similar to mixing colors for painting but the last color on top is the more dominate hue. I highly recommend having some scratch paper to practice on before committing it to your final piece.
5) Light colors and similar colors are easier to blend than dark and opposite colors. This is ink we are talking about so deep colors stain the page easier than lighter ones so that impacts blending.
6) This tip only works for Copics - The Colorless Blender marker is not for blending but rather pushing out ink. Some people refer to it as removing ink but what actually is happening is the rubbing alcohol in that marker forces the ink through the page. On the topside of the paper the removed ink looks lighter or completely gone but flip over the paper and you can see it seeping through. So again, that is why good paper is nice to have. The coolest ways to use this marker are for special effects, like frost or something you want to look faded or grainy.
7) Marker tip shape preference is up to you. Some like a chiseled tip because they do more architectural or concept coloring. Personally I prefer the sketch tip (brush tip) markers. They allow lots of control over stroke thickness and provide a more painterly look.
I hope I didn't drone on there too long. I hope this info was helpful in understanding how to start your markering. Really the only way you can learn is by just diving in and testing them out on practice art. Have fun and good luck!
This is my process for Whetstone