Pickpockets
Pickpockets are on the lookout for foreign visitors who appear careless about their belongings. They may pull elaborate tricks to separate a person from his or wallet, or they may swipe your cash and credit cards from you with nimble skill. Be especially wary in tourist areas, such as Arbat Street and crowded places such as the metro. Don’t expect a backpack to be a safe bag bet; instead, invest in something that you can clutch close to your body or purchase a money belt. Always diversify, keeping some money in a separate location so that if you are pickpocketed, you'll have money elsewhere.
Because pickpocketing is a real danger, carrying your passport with you is best avoided. However, do have a photocopy of your passport on you in case you get stopped for any reason by the police, who may ask to see it. Also, photocopy the page in which your travel visa appears and any other documents that relate to your stay in Russia.
Respect
When visiting points of interest such as Lenin’s Tomb, it’s important to pay the requisite amount of respect. Security is strict for this novel Moscow attraction, and long queues may tempt you to fidget or make jokes. Just chock the guards’ no-nonsense attitude up to being part of the experience, and for goodness’ sake, keep your hands out of your pockets and the grin off your face! If you plan to visit any Orthodox churches or cathedrals while in Moscow, then you must pay attention to how you dress. Dress requirements for Orthodox churches include covered legs and shoulders. Women should have their hair covered, and men must take off hats.
Customs Regulations
If you are shopping for art or antiques, be sure to purchase from a dealer who can provide you with the necessary forms that will be required to take the purchase out of the country. Keep these forms and your receipt to show to customs agents before leaving Russia. Do note that items over 100 years old are not permitted to leave the country.
Registration
Any traveler in a single destination for three days or more will have to register so the government can keep tabs on where its guests are at all times (even Russian citizens have passports for domestic travel and must follow their own system of registration). Hotels will typically register for you, which will require you to hand over your passport and visa. These will be returned to you with the necessary registration documents. You may incur a fee for this service, with large hotels charging minimally and smaller hotels charging quite a bit more.
If you are staying in a Russian home, registration should be completed at the local police department.
Electricity
To avoid frying your electronic devices, be sure to have a 220v converter with you, complete with round, two-pronged adaptor.
Water
Visitors to Russia are warned not to drink the tap water. Water should be boiled before drinking, though showering is safe and the amount used to brush teeth is generally not harmful.
Get a local SIM card
A local sim card that makes one's smartphone usable while traveling through a foreign country. But with ready access to resources like maps, language translation apps, and so on.
Moscow is swaddled in strong, high-speed LTE signal available from a number of affordable providers. Look for company names like MegaFon and Beeline, which offer prepaid Russian sim cards compatible with your unlocked smartphone. It costs as little as $1 USD per day for unlimited data.
Learn a few Russian phrases
Demonstrating even limited abilities with the Russian language will go a long way toward getting you a friendly atmosphere.
DO check the events calendar
During major holidays – the first week in January (between New Year’s Day and Orthodox Christmas) and the first week or two of May (around Labour Day, or May Day, and Victory Day) – Moscow empty out. Despite this, both cities are festive during these times, with parades, concerts and other events, but museums and other institutions may have shortened hours or be shut altogether.
Take a walk
Start with brunch at Strelka (in summer, have lunch on the terrace), before setting off on a long, lazy walk along the river embankment. Call into the Tretyakov (see above) and then walk on through Gorky park which, in recent years, has been turned from a gloomy weed-strewn mess into a fun and pleasant space, full of cafes and activities. Continue all the way along the river until you reach Sparrow Hills (Vorobyovye Gory), from where you can take the metro back into town.