Blue tape is better than plain old vanilla masking tape, but it's not ideal - it still has a "crepe" like texture under which paint can seep. It's fine for house painting, but not so good for detailed models. It's better if you burnish down the edges and/or shoot base color or clear before putting on the next color layer - this fills the gaps in the crepe texture with base color, preventing bleed through. However, often times you shoot additional layers before the earlier layers have fully cured - I know this is not ideal, but it's a fact of life, too. A heavily burnished tape edge is more prone to lifting the base layers in this situation.
A better tape is fineline striping tape as it's more smooth (less chance for seepage) and flexible, so it can curve and conform to irregularities more easily. Hard burnishing isn't required so lifting of base layers is less of an issue - just make sure the edge is completely stuck down (a light burnish with an exacto handle or your fingernail).
There is another tape product I've used with good results, but the name escapes me. It's a brown paper tape with sticky stuff only along one edge. It is quite smooth so seepage is minimized and not super tacky so it's not prone to lifting base layers.
Micromister has good advice - parafilm sounds ideal if you have a decent source of it, and peeling the tape up soon after shooting (before full cure) helps in getting cleaner lines.
Finally, don't flood the paint on - that invites seepage. A technique to control this is to shoot a light mist coat to help seal the edge but not induce seepage, let it flash off, then shoot another layer to get the proper build.