Following is an example of the trick training that Trigger and I do each day and how I fit it around daily horse chores and riding.
Horses learn much quicker if they are taught tricks in several, enjoyable, short sessions (about 5 minutes each) rather than one long one.
The perfect time to do a bit of trick training is when you are going out to your horse to feed them or do daily chores.
This also means that you are adding some fun into your routine rather than just making it all work for your horse (and you).
I recommend working on only one NEW trick each day but also practising tricks your horse already knows well.
8.
00am - Mix up Trigger's morning feed

• Practice a trick that Trigger already knows such as Kiss (1 minute).
  
• Practice touching a handkerchief, which is the start of teaching Trigger to take it from my pocket (2 minutes).
  

8.
05am - Feed Trigger & take off his rug 10.
00am - Clean out water trough

• If Trigger comes up to me while I am in his paddock (which he does 99% of the time) then we will again practice touching the handkerchief (2 minutes).
  

1.
00pm - Bring Trigger in for a ride

• Practice calling Trigger in.
  He will usually come cantering over to me when I call him (1 minute).
  
• Again practice touching the handkerchief (2 minutes).
  

1.
05pm - Saddle Trigger up

• While saddling, practice some tricks he already knows such as lifting his feet by just pointing at them and lowering his head for bridling (2 minutes).
  

1.
10pm - Go for a ride 2.
00pm - Return from ride.

• Practice tricks Trigger already knows such as moving over by just pointing at his side and again picking up his feet by just pointing (1 minute).
  
• Practice touching the handkerchief and encourage him to mouth the handkerchief (2 minutes).
  

5.
00pm - Mix up Trigger's evening feed

• Practice a trick he knows such as backing up by tugging (gently) on his tail (1 minute).
  
• Practice touching the handkerchief and encourage him to mouth the handkerchief (2 minutes).
  

5.
05pm - Feed Trigger & put his rug on

• Ask Trigger to give me a goodnight hug (30 seconds).
  

Total Trick Training time = 16 minutes The schedule above shows that I have been able to fit six short trick training sessions into a day.
No special preparation was necessary (except I needed to take a handkerchief and some treats with me - or I could have used some of his feed).
The next day I would follow a similar schedule but ask Trigger to do more with the handkerchief, if he is ready.
For example I would encourage Trigger to actually take the handkerchief in his mouth.
You might not be able to spend as much time with your horse throughout the day but if you visit your horse even once a day, try to fit a short training session in several times during the visit - at the beginning and end of everything you do.
If you practice several times a day and make the session short and enjoyable you will find your horse will learn super fast!