Pretty much any Self-guided meditation or visualization can help. take a little time to be still and become aware of your breathing until you feel like you are more-or-less focused on the present moment. As opposed to thinking on the future or past. Once you feel like you are as close to the here-and-now as you can get, use whatever imagery you are already familiar with to visualize a recognition of the stresses and negative energies influencing you, and then those images being released or sent away from your presence.
Some use sunlight to shine away the energy, others imagine or use flowing water, and/or salt. Some use smoke from different kinds of incense, some call on help from their guides/guardians as well.
Another way to shed the stress is to get yourself into a natural setting where you can just sit, take a breath, and watch nothing in particular. Exposing yourself to natural light and natural colors helps to reset the system and tends to inspire a sense of restfulness if you can manage to take some time to just sit and be still for a while. if there is a pond or lake nearby you can always go with a small bag of cracked up corn and feed the ducks. I find that simple gesture to be rather therapeutic.
Also, random acts of kindness are unusually potent and uplifting. if you are feeling down in the dumps and in a rut, go out and find someone to help with something. it sounds really corny, but when a person does kind things it promotes kind and happy thoughts as well. It triggers a sense of satisfaction and worth that knocks the hell out of any negativity that might be trying to cling on. A personal favorite is to whip up a sandwich or two, and hand it along with a bottle of water to the first person I see who is asking for change while I'm on my way to or from work. or you could just pick up the trash from a neighbor's yard. Or if you see them doing yard work, grab a shovel and some gloves and go help for a half-hour or so. Or of course shovel a bit of snow if you get it during the winter months.
lol, well, there aren't many tools required most of the time [unless you hope to carry an item to bring these things] but it will take time and daily practice to be successful. [not a ton of time, 5 minutes and work up from there, but as the old saying goes, if you can't meditate for 20 minute, meditate for an hour] check our Larks article on grounded for an easy method [personally i ground while meditating, but still it's visualization and feeling the energy] you could also try a barefoot walk to hugging a tree [odd as that sounds this can connect us directly with the earth and ground us] tai chi and yoga can also work [be mindful while you work] you could also cleanse away energy in the shower by visualizing/feeling negative energy being washed away.
staying positive is also tricky, and a daily skill you need to work on [but it could be harder depending on some factors. i've got depression, and it can be a real uphill battle some days] carrying a journal with you and using it often can be a huge help, you can use it to write down things you are grateful for throughout your day, or you could write down negative thoughts you find yourself thinking and replace them with a positive work ['stupid' replace it with 'i'm learning' 'ugly' replace with 'pretty'] an affirmation or mantra wouldn't hurt either [though you need to be a little open to it] a really uncomfortable one but really works is to look into your eyes in the mirror and say 'i'm beautiful' [or smart, or funny, or whatever your thoughts tell you you're not] then wait, your mind will fight back and think the whole thing is stupid, just keep telling yourself you're perfect or whatever you chose to say, eventually your brain will quiet down and you can stop. repeat this every day [first time i did this i laughed and rolled my eyes, had to try it a few times and try a few phrases until one really sunk in. i went with the last line from the chorus of Pinks song Perfect, but i've always admired her, so you might need to reflect for a bit]
just remember we all have highs and lows, no one is 100% positive 100% of the time, it's recognizing when to be angry, when to be sad, and when to be happy that is important. just don't let it consume you, have your cry, then pick yourself up. when you feel really low you might consider kids help phone or suicide hotline [don't let the name scare you] they're there to talk when you just need someone, or just to vent, or to ramble and have some stranger to comfort you. [sometimes a third party to talk to really helps]