Briefly, communication with deceased loved ones cannot be forced. Obsession will only block your attempt. Relax and let go. Don't complicate the process. Soulful signs from our deceased loved ones are all around us if we look for them. Messages will come in simple forms, like a familiar smell or a loving thought, and little things do mean something. There are no coincidences.

You may have to wait until the powerful emotions of acute grief subside for your loved one to get through, but welcome their presence when they do.

From Healing After Loss by Martha Whitmore Hickman,
Perennial Press, 1994, December 12 entry:

...as we dwell in memory on our experiences with the one who is physically gone, his or her psychic presence, rather than being confined to the body we knew and loved, seems somehow to expand and surround us with its gentle understanding, its compassion and love.

So we enter upon different kinds of conversations, often exchanges without words. We seem to come to a mutual understanding and appreciation for the goodness and the difficulty we were in each other's life. We're able to smile...at all the flurry, and to relish, instead, the deep love and peace. Dear One, continue to be with me, as I will with you.