Gratuities are for those who have preformed their duties and have done them exceptionally well and above your expectations, they are usually provided at the end of the night (usually in cash). Most tips are at the discretion of the bride & groom. I can tell you from experience that when a gratuity is received or presented no matter what amount the vendors are extremely happy.

Alternatively, you’d also be surprised how far a thank you card, testimonial for a website/portfolio, review on their services on a website, or perhaps some photos from your wedding goes! This is something you could do to thank your vendor for a job well done that they might just appreciate more than a gratuity.

Here are some vendors you might want to include into your budget.

Caterer - Usually this is built into the contract price, usually 15-18%. Unfortunately if they do not live up to expectations you cannot take back the gratuity you will need to speak to the vendor after the wedding.

Makeup Artist/Hair Stylist – Depending on the services and how early they had to come in, a tip of 15 – 20% is typical.

Limo Driver/Transportation – Usually a tip of 15 - 20% is provided, sometimes it is included in the contract, so read your contracts.

Wedding Planner – Any gratuity is at the discretion of the bride and groom.

Photographers/Videographers – Gratuities are normally presented but if your photographer/videographer went above and beyond what you had expected, typical amounts can be anywhere from $50 – $100 and more.

Ceremony Musicians – Typical amounts range from $50 - $100 depending on the amount of musicians and length of play.

Officiant – Any gratuity is at the discretion of the bride and groom and can range from $20 on up. Be careful when tipping if you are using a religious institute as sometimes it would have to be in the form of a donation to the church and not to the priest/minister/reverend etc.

DJ – When a DJ has done their job right, no one wants to leave! They most certainly appreciate any gratuity but it is not expected, typical amounts range from $20 - $100.

Floral Designer – A gratuity is not expected but is very much appreciated. Typical amounts start at $20 and go up.

Cake/Baker – As with the florist a gratuity is not expected by much appreciated, and is at the discretion of the bride & groom.

 Remember most of the time it is not up to the contract, but to you as gratuity is a thank you for exceptional services not a must, nor is it expected. Very much appreciated but not expected.

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Where do you start. Well the best way to start is to think of what you want, and who is going to pay for it. Write down you vision, do you want a large (300+) wedding with a sit down meal or a small intimate cocktail hour. Figure out how much you, your parents, your in laws are willing to spend. If you only have a $10,000 budget you won’t be able to have a large wedding with a sit down meal, and you need to figure that out in the beginning otherwise you will disappoint yourself.
 
Set your priorities. Is photography your number one priority or is the venue, or something else? You could have a sit down dinner for $10,000 if you sacrifice the amount of people coming. Your vision can happen on your budget, but you have to figure out what you are willing to sacrifice in order to obtain your vision.
 
Once you have a vision, priorities and budget, you can move on to the fun things. First and foremost pick a date, each vendor has many inquiries each day, and they will ask you your date. It is hard to give a quote to someone if they do not have a date, because the vendor may not even be available thus wasting your time. Your best bet is to ask if they are available first and then price. And the first vendors I recommend starting with are your venues, photographer, and wedding planner (if you choose to do so). Those are usually the most important, and the ones that usually book up the quickest.
 
A few more tips:
Keep a binder with contracts
Get EVERYTHING in writing, even small amendments
Keep on top of your budget
Email is a great way to communicate (emails hold up in court - just in case)
Ensure you have a contract with the vendor and make sure you receive a receipt
Google the vendor, see what comes up (company and personal name)
Ask for references