Care should be taken when attempting to communicate with any entities. You will want to make sure you are targeting benevolent entities. Here are some easy steps to makes sure of this.
1. Start with a prayer of protection before and after any sessions you have. Ask your angels or guides to protect you. Envision yourself and any others involved surrounded by white light.
2. Request that you only wish to communicate with entities of positive polarity, ask them to come through in the name of Love and Light. Specify entities who have went to the light. Earthbound entities tend to be quite dark or negative.
3. You should never provoke an entities or request them to manifest to
prove they are real, you never know what you might get. You will most likely have a negative experience.
4. Be very specific with your line of questioning. Create stipulations after your protection prayer. Its a good idea to specify that any entities who do not come forward in the light and love of the one infinite creator will not be tolerated.
5. Ask the entities if they come in the light/love or who they serve. If they do not answer, order them to leave, while maintaining positivity and intense loving white light surrounding everyone.
6. Do not let your emotions go negative, as this will feed the negative entities. Loving thoughts and attitude will discourage a negative entity.
These steps will not eliminate the risk, will only minimize the chances of a negative experience.
Even tarot cards can provide a portal for negative energies. You should always surrounded yourself by love & light utilizing them. Any medium that you use to communication with spirits are only tools to focus your own psychic sensitivity, and are a good ways to utilize your physic abilities. Just maintain your protection to maximize the positivity.