Use fluent api for mapping entities in efficient way. For example you can map the one to many relationship between shoe and colors in following way -
public class ShoeMapper : EntityTypeConfiguration<Shoe>
HasMany(x => x.Colors).WithRequired().HasForeignKey(x => x.ShoeId);
Apart from this you should create a separate table
then a junction table
[fk_Shoes_Id, fk_Colors_Id, varchar_SampleImage]
to map relation as per normalization recommendation.